I'm on my third iPhone case in less than a year. I'm still not sure if I even like this one a lot. Time will tell.
My first one was the Griffin Elan Form case. It's a hard plastic shell with a soft, black, leather-ish outer shell. It's soft to the touch but still solid protection if dropped. I had the same type of case for the iPod Touch I used to have and loved it. But on the Touch it was slightly different - the case was a snap together and covered more of the front of the device. On the iPhone, it has the removable bottom piece and barely even wraps around to the front. Eventually the two halves started to loosen up and it would come loose when I pulled it out of my pocket. Kind of annoying.
Then I got another Griffin case... apparently thinking that it would somehow be better. I bought the Griffin Graphite Elan case. It has kind of a fake Carbon Fiber finish to it. Same idea though, hard shell but soft to the touch - still with the two halves though, top and bottom. The idea being that if you have a dock for your phone, you can easily remove the bottom half to place it on the dock. Eventually it kind of succumb to the same loosening as the first one. That... and some of the outside "fabric" started to peel back a tiny bit. Lame.
After I bought her her iPhone, Jen got on of the iFrogz Luxe cases. This case was intriguing for one reason and one reason only: it had what amounted to a small latch to keep the two halves together. This showed potential considering my other two cases had started to separate. But the case itself felt a bit generic and of not-so-great quality. The fit was not fantastic either. You could tell even with the "latch" that it was still a bit loose overall. Not what I was looking for.
Today I am trying a whole new brand. This one is from Speck Products and is just labeled a Fitted Case and in my choice is a black and white plaid pattern. This is a two piece case but more of a front and back design than a top and bottom. And since this one "snaps" together I'm hoping it will actually stay together. Of course I thought that about the first two, so who knows.
To be fair, the first two are nice cases - and if you do need the ability to take the case apart to dock it, they work quite well. And the Graphite one looks awesome. I'd still recommend it if you need that feature. I'll report back on the Speck case if I find any real faults... stay tuned.
If this one doesn't work out, I may look into one of the silicone one piece cases. I don't ever need to take mine apart, so it might work. I just don't know if I'll like the feel. Who knows...