Ah ... depends on the camera and whether or not you don't mind a rather largish housing. Some Ike housings don't give you full function over your controls. And some don't really fit all that well. I had a friend with an S95 who had problems with how well her camera fit inside the Ike housing ... she had issues with some buttons working once the camera reached a certain depth (pressure). She figured out how to jury-rig it to work ... but it involved cutting up pieces of foam and stuffing them around the camera.
If you're going with a 3rd party housing of any sort, it's always best to do your homework and talk to someone who's used them with the camera you're using ...
... Bob (Grateful Diver)