We have quite a few Scubacam housings at OpTex Rentals here in the UK. They are supposed to work down to approx. 2M (6 feet in Yank Speke) although we tend to recommend people just to use them on the surface. Having said that, I can't think of any case where a Scubacam has leaked, and I'm sure that plenty of people don't always follow our advice to the letter.
1) Do check out the housing without the camera in place first. (use a dummy weight)
2) The Scubacam is made of latex rubber. You do have to be careful how you treat it especially the fairly thin finger holes. With most housings, the camera is a tight fit but it DOES fit snugly if you have a little patience. Forcing things is likely to damage the housing.
The only real problem I can see is the 6 feet limit. how do you know you are exceeding 6 feet? Remember that you can also use the housing on the surface. It's great for very wet weather, dust and sand etc.
I have used the Scubacam bag with an SR3HS.The shoot consisted of shots in a swimming pool(handheld) down to about 3 feet.
All points made by Brian Rose were true with my Scubacam experience. My 1stAC had a bit of trouble getting the camera in the bag.
I do recall having to swap out the Canon 8-64mm for a 10mm prime because the 8-64mm either would not fit or it was vignetting at 8mm. I do not recall but there was a some kind of problem with the zoom. The 10mm prime worked fine.
From what I remember the viewfinding system was not that great. My shots were thankfully handheld with a capped off finder, so it really wasn't an issue.
Also, we could not see the footage counter through the bag so that became a time consuming issue as well.
But all in all, a great, very lightweight, water tight housing. It's low profile and surface area made for easy underwater dunking.