I am looking to buy into an underwater camera system but don't know much about the various housing options. As I understand it I will pick a housing for my SLR body and then need to buy tubes and domes to attach various housings. If when I change cameras I will need a new housing but can reuse the tubes and domes. For this reason I figure I should put some good thought into which brand to buy. What companies are recommended? Currently I'm looking at an aquatica housing I found on ebay but don't want to get stuck with second rate equipment just because its cheaper. Any Thoughts>