My technique will probably not be suitable for the type of diving you are doing in N.J./Pa. with colder water, possibly bulkier equipment, maybe more stressful conditions........but for warm, open water, recreational diving I use a 6 cu.ft. pony held to the plate with velcro straps (usually used for argon bottles). This sits under my left arm and hose is routed behind neck, down my right side, and held to the waist belt D - ring with rubber snorkel keeper. Bottle is small, air limited, and will allow only minimum time to solve problems. The advantage for me is that I actually will dive with this set up, and can travel with it easily.It is small enough to be convenient and is not noticeable during the dive. I have never had to use this, other than for practice (which I do). I dive this with a 5' primary and a bungeed short hose back-up with no problem. Bear in mind that this is not enough gas for anything approaching technical limits or for very cold water or high currents where SAC will be elevated. My objective is to have a system that I will use regularly that will allow me to either reach another diver or get to the surface alive.