In trying to find a top notch video player for my Tbolt I was disappointed by the lack of good information. Posts on the topic in various forums were either quite old or simply opinion with no backing evidence. As such I picked what appeared to be the top 3 video player options and tested them.
I did not do really thorough testing of the options, UIs or audio/video quality. The main purpose of my testing was to determine which player could reliably play the widest range of video types. I was hoping to not have to re-rip my large movie collection for occasional watching on the Bolt. Unfortunately, with the existing players this is not going to be feasible. One significant show stopper other than the players themselves is the 4 GB file size limit for the SD card. I've heard there may be optional formats that work around this limit but haven't found actual instructions nor proof of this. To test I selected a wide range of videos, wmv, m4v, mkv, avi, vob. They had a variety of file sizes audio/video encoding, resolutions, audio and video bitrates, etc. All however are feature length movies.
If I had to choose a winner based on overall ability to play diverse files it would be Moboplayer. However, this is not much of a "win" since it played only half of my test movies well enough to call them truly watchable. Vplayer was in 2nd place, however, its big limitation is its 7 day trial period.
Unfortunately none of the players played either of my personal prefered format (mkv files) except for one file played properly by Moboplayer.
If you want to encode in a way compatible with the most number of players a m4v file is the clear winner with simple 2 channel AAC audio.
Although not prepared in the cleanest/easiest way to read the complete results of my test are available here in this attached spreadsheet.
I'm anxiously awaiting VLC for Android and hoping it is anywhere close to as good as the Apple OSX version of VLC. This player simply plays everything one can throw at it.
I certainly welcome referrals to strong candidates for further testing.