One of the things I like about DSS is that he wants your rig to be *perfect*. However, I'd dive your current BP/W without hesitation both cold and warm.
Exactly. Size Large may be ideal for a diver over six feet tall, but Medium will probably feel just fine. As for the LCD 30 wing, when I was choosing a DSS wing with Tobin's help, he told me that for my warm-water diving I could go with the 17 or size up to the 28 or 30. A 28 or 30 is probably more lift than truly needed, but the only potential disadvantage is that you are swimming around much of the time with it only partially inflated, meaning it's sort of floppy and adds drag. Drag is bad. Streamlining is good. A 17 is probably a joy to dive in the tropics when you're wearing a thin suit, keeping you nice and streamlined. But a 17 is not going to be sufficient if you also want to dive in cooler water with 5-7 mm of neoprene, as I do on occasion. So I chose the Torus 28 to give myself some flexibility. And it works just fine. If I am less than perfectly streamlined sometimes, it is hardly noticeable to me. Also, some people (perhaps divemaster or instructor types) have commented that they prefer a larger-than-necessary wing so that they can have extra buoyancy in case they need to assist another diver at the surface or to enable them to carry a couple of extra weights to hand off to a diver underwater who finds he's underweighted.