I concur - and here is my [long] story.
I recent purchased 2 seidio active cases one from Amazon and one from seidio directly (I had to do that cuz the wife wanted a particular color, and I had doubts so I wanted to be able to return to the amazon vendor and get money back). The previous set of cases I had were the "premium rubberized cases" found on Amazon for like 0.01 or something crazy like that. Those cases lasted a couple months but ultimately broke. The tabs securing both top and bottom halves were microscopic. A few of the tabs broke upon installation but there were enough to keep the whole thing together. They were alright for the time they lasted and for the price is a great way to just have something on the phone. At the time the otter box wasn't available and since my previous experience with them (blackberry storm) was fantastic, it was a no brainer. Then I came across a large amount of negative comments. I took the opportunity to try a new [to me] brand and that was seidio. I went with the active cases. The surface cases looked too much like the cheap "premium cases" I had and I wanted some actual rubber included for max protection. When I got the cases it was clear that they use a thicker, stronger plastic. The back half is a great piece. It has nice locking tabs that appear to be very durable. The rubber insert is nice and the button covers were great. Then I looked at the top half. It was definitely thicker and covered more of the phone than the cheap cases, but they only had 3 tabs and they too were micro thin. I was sad about that but figured I'd give it a try since I just paid almost 30 bucks each for them. I was at a mattress store (no really, I was) and holding my phone when for no particular reason it slipped out of my hand. It fell 18 or so inches from my hand down to the (admittedly) firm mattress. I guess it just caught the corner because the top half went flying. I was shocked, but thought, that’s okay, just because it came off doesn't mean it was broken. Well actually yeah, the large top locking tab was sheared off making it impossible to use the case. It’s pretty ridiculous for a $30 phone case to fail because it fell onto a mattress. I can understand concrete, but a firm mattress? That’s just preposterous. Although not surprising after you look at the impossibly thin tabs. Anywho I returned the case to the Amazon vendor and I am getting my money back. The case on the wife’s phone is from seidio, so WHEN it fails I’ll just have to get a replacement (hopefully) but there’s no getting money back. Then again her phone lives in her purse 99% of the time so I give it more time.
Bottom line: no case, at any price, from any company, can sufficiently protect a sliding phone. Period, end of story. The mechanics make it impossible since there is no way to secure the top half to the phone with strong-enough tabs to make it safe. The only solution is a universal pouch, and hopefully when you’re actually holding it you don’t drop it. If you do, you’re SOL. We can’t even use silicone cases. The only option would be one of those films that you put around the phone, but that won’t help against a 3 foot, corner impact on concrete – which, btw, my black berry storm with otterbox defender case soaked up like nothing.
Next time I just won’t get a sliding phone – even though I like the physical keyboard, sacrificing protection for the keyboard is dumb.