Otterbox has a great reputation for making quality cases, but they missed the mark on this one. It just fits the HTC EVO 3D too losely. A soft case like this must be snug, but this slips on and off the phone very easily. Also, the material is very sticky on the outside, so pulling it out of your pocket is more awkward than it shoudl be, as it pulls your pocket out with it, and half the time the case comes partially off the phone.
It does seem like it is protective, but thats because its fairly thick (for a silicon case). Another plus is that it includes a screen protector.
I used this for about 2 weeks, but it was driving me crazy. I ordered a Case-Mate CM015750 Tough Case for HTC EVO 3D which is working out much better. It actually fits the phone properly, and the hard outer shell keeps the soft skin firmly in place. And its not even any bulkier than with the Otterbox Impact on it.