I really liked the Maxx so I upgraded to the Maxx HD. I liked the HD, except for one very glaring feature which drove me away from the device entirely.
-Love the form factor. Felt very solid to hold on to.
-Really liked the interface. Quick menus were functional, I liked the quick contacts widget in particular. The overall android experience the Maxx HD provides was good in my opinion. The stock keyboard works really well, and autocorrect on the Maxx HD is pretty darn great.
-Reception and call quality was fantastic. No issues whatsoever on either end when talking to someone.
-Speed/data connectivity was much better compared to the Maxx. The Maxx would drop my 4G signal more often than I would have preferred.
-Multitasking and switching between menus, homepages, etc... was awesome. The snapdragon processor in the HD compared to the Maxx was the right choice. I experienced little to no lag.
-Battery life. Averaged around 28 hours per charge with moderate to heavy usage. A LOT of streaming. You cannot touch the battery life on this phone compared to others.
-CAMERA. Motorola actually managed to take a step back with the Maxx HD. I took some photos on my regular Maxx in comparison and got noticeably better shots. I describe the HD's camera as simply inconsistent. Predominantly the Maxx HD suffers in low light situations. Heck, it even suffers in slightly less light, and in many cases would suffer in good light. It was all over the place. Looking at the list above it seems silly that I would trade the phone for 1 peripheral feature, but I did. That peripheral feature is actually important to me based off what I use my phone for, and certain environments I am in. I ran this camera through the ringer and found that the main issue was that the flash did not stay on long enough to properly expose the photos in low light conditions. Furthermore, the flash, in my opinion, is not bright enough. Also, autofocus would misfire, or not fire at all, most of the time. I downloaded approximately 15 different camera apps (Camera+, Vignette, Camera 360, Pudding Camera, you name it, I tried it). Nothing really fixed the camera. Pudding camera had probably the best overall results, but even still, about 60 percent of the photos still came out a blurry mess. One thing I figured out on the camera that helped was, if you turn flash to "on" (not auto) you could double tap the screen and it would keep the flash on for as long as you held your finger on the screen. What I would do is let the flash stay on for approximately 4-5 seconds. This would allow for the phone to dial in better lighting, and further clarity. However, even with this manipulation photos still came out in different colors, exposures, and saturations. At the end of the day there is no reason you should have to do all of this to still end up rolling the dice on a somewhat useable photo.
-The camera is second to none. Photos on this phone are simply awesome, consistent, and feature rich. The Maxx HD had very minimal photo options. The S3 allows you to manually control ISO, Exposure, and various other shooting modes along with the option to customize shortcuts. Low light photos are phenomenal for a phone camera (even at a distance). I honestly think the FRONT camera on the S3 is nearly better than the rear camera on the Maxx HD. Not kidding.
-Reception/call quality is great so far. I was pretty nervous going to Samsung from Motorola, knowing Motorola generally performs well in this category. So far I have had no issues. People say they hear me fine, as I do them. In fact, the S3 has a built in equalizer to adjust incoming audio to your preference.
-Media interface. Access to photos is about the same as the Maxx HD, but the music player and music widgets have a slight advantage on the S3. Access to music just seems to be easier on the S3.
-Sound quality. The sound quality of audio produced on the S3 is better than the Maxx HD. At least, I think so. This is somewhat of a subjective category. I had a few different equalizer apps running on the Maxx HD which helped the audio a little, but the built in equalizer on the S3 is more well rounded and easy to access. I have confirmed this by running both phones on a Jambox, Big Jambox, my car bluetooth, the Motorola stereo SF600 headphones, iPhone headset, Beats audio headset, stock headset with the S3, in ear and over the ear headphones, the Motorola elite sliver. You name the headset I've tried it on both. I stream a lot of Spotify and local audio. The S3 produces better quality overall.
-Touchwiz. Honestly, I am kind of "meh" about Touchwiz. But I have found some rather useful features in it that give it a slight advantage over the Maxx HD. The way you uninstall apps on this phone should be a standard for ALL android phones. The same goes for how you can hide applications.
-Battery life. Well, its not the Maxx HD, but it is definitely good enough. With heavy usage throughout the day I am getting down to 20% after 18 hours or so. Thats not bad for a 4G phone and 2100 MaH battery.
-Screen quality on the S3 is awesome. I would say it looks better (better colors) than the Maxx HD's.
-Form factor. The form factor is not necessarily bad and this is personal preference, but I much prefer the feel of the Maxx HD. The S3 had nearly slipped out of my hand multiple times due to a combination of where the lock button is place, the slick-plastic back of the phone, and how far the screen extends to the edges of the phone (your fingers can easily wrap around to touch items on the screen you do not wish to). I find myself changing the volume on accident all of the time. All in all, if I ever drop this phone, or should I say WHEN I drop this phone, I will be worried. The Maxx HD almost felt like you could drop a brick on it and have it be okay. Also, I was not looking forward to the form factor of this phone because it was over the boundaries of what I considered "too big". The Maxx HD was just big enough. However, that being said, I am quickly coming around to it and it is looking smaller every day (so to speak).
-Some of the wireless connectivity like wi-fi or P2P sharing can bog the phone down a little.
-Compared to the Maxx HD, speakerphone is not terribly impressive. The Maxx HD had an awesome speakerphone, however, this is a feature I rarely, rarely use. But I do notice the difference in quality.
-Some of the Touchwiz stuff is annoying. Creating folders is a 2-3 step process, whereas, the maxx HD you simply drag one app over another and its done. I do use folders a lot. Again, not a terribly big deal but is noticeable. I have most of the motion controls off. They seem like they would be more of a battery drain than anything else. One more thing, the whole "nature" theme of Touchwiz is dumb. The lock and unlock sounds, which I do feel I need to use, are cheesy (this is a little nit-picky).
-Speed. Moving between menus and the interface in general is fast. But the Maxx HD simply felt faster. One quick tip: The home button has a noticeable delay from when you press it, to when it goes back to the home screen. Turn off the "double press to engage S-voice" feature, and its fixed. Also, the photo gallery has a slight delay discrepancy between the speed your finger pushes and the actual movement of the photo tiles. Download "Gallery ICS" and the issue is solved.
-S voice. Honestly, S voice gets a lot of flack, but I don't think its THAT bad. Its not up to par with Siri, but I think it is as good, if not better, than Vlingo. S voice still has a ways to go. I am using it, and getting decent results out of it, but it fails to connect to the server more often than it should. The "wake up command" feature only works half the time.
- Probably the worst feature on the S3 is Samsung's patented auto-correct/keyboard software. I don't even mind the look or size of the stock keyboard on the S3, but the autocorrect is horrible. Absolutely horrible. I downloaded "Jelly Bean Keyboard" and it makes text entry nearly identical to the Maxx HD. Also, I use Swype most of the time anyways so this "Con" is easily rectified (the new Swype Beta is fantastic). However, going off of stock principles the S3 loses big time in this category.
Overall I am very happy with my exchange. I tried to be as fair as possible in this assessment. The reason I posted this is to help anyone who might be in a similar predicament, or assessing which of these phones to pick up. Feel free to ask me any additional questions. I'd be more than happy to help or advise.