Ok I've had my cases (well only one is a real case) for about a week and a half. It's the HTC geli skin. It fits good, even better than the one they make for the EVO. It has cut outs for the FFC and sensors, and adequately protects the camera. It makes the power button more difficult to use, but you can always unlock it with the trackpad. Overall I'm satisfied (I'm a bigger fan of hard cases honestly).
I also got a Golla bag, but I can't remember which one right now. The one I got is a really tight fit. Not so much that I worry about the phone, but tight enough that you'll miss a phone call trying to remove it. Oh, and it doesn't fit with a case on.
The one I'm happiest with is the Mobi pouch. It's big, but the phone will fit in it with the skin on. It's actually a pretty good fit with the skin. My favorite combo so far is the skin and Mobi pocket pouch.
The SPE screen guards are a mixed bag. I love anti-glare screen guards, and in that respect these don't disappoint. BUT I can't get the bottom edge to lay down all the way. I even tried another one thinking I messed it up somehow. It just won't lay down the way it's supposed to. It's not on the screen itself so it doesn't interfere, but it's annoying to have a line at the bottom that won't lay flat.
On a side note, I noticed that Seidio makes the Innocase for the myTouch 4G now and am hoping they show up in the AC store. I went through a few of them on the EVO to get a good fitting one, but once I did it was the perfect case. The also make it with a belt clip.
seidioonline.com