Hi Again,
Yes I am very familiar with OMS. We are an authorized dealer for them as well as Dive Rite. As a matter of fact, they are right down the road from us. John G. has visited our store personally. As far as Dive Rite vs OMS, both offer excellent equipment. There is a lot of hype as to who is better. The only way to answer this is for you to try them both out before you make a decision. I actually use equipment from both, plus mix/match accessories with no problem at all. For side mounting, I use a DR TransPacII converted into a Nomad. Before my back injury, I used an OMS SS Backplate, 94 lb Dual Bladder Bungee wing and DIR/Hogarthian style harness. As far as the wing "Taco" effect around the bladder, DIR says this is how it should be done. However that is not written in stone, and if you don't like that effect, I can show you how to prevent it with either DR or an OMS bladder. The big thing is not to believe that the biggest bladder is always the best, and from what you said and what you are looking at, I think you already have that part covered. Both DR and OMS offer small bladders in the 30 - 40 lb range. Again the best way is to try them with your full kit, and see which one works best for you. You cannot go wrong with either brand.
Stop in anytime - the coffee is always on, and someone is out diving almost every day. Hope to see you soon.
Stay in touch, and let me know what you decide.
Safe Diving,
George
PADI MSDT