My quest for the perfect photo BCD has led me from using traditional BCDs, a Zeagle ranger and finally backplate and wing (which I love).
The beauty of this system is multifaceted. Firstly it is modular. I started with a stainless steel backplate (zeagle) and used my old ranger wings. I then switched to Hollis wing (for single tank) and Halycon wing (for twin tanks). I bought my harness at a hardware store.
The 'D' rings are strong enough to hold a housed SLR on land. It frees your chest from paraphernalia. There are no cummerbunds, tightening straps, quick-release clips etc... to get tangled in your strobe arms.
It improves you trim (not your buoyancy) It is comfortable in the water (but not out of it).