You need the option of a build in STA of course with cutouts through the wing long enough to accommodate different backplates and with the right width between the slots (unlike the Apeks slots). Otherwise the bands stretch the slots... no clue what Apeks were thinking when they introduced these slots. Probably that noone will use them.
Otherwise what's the point of modular wing If I always have to carry everything on every trip.
This however may be good and is something that I cannot find easily. I wanted to have a chest strap to minimize the movement of the entire gear kit against my body when I am wearing only a rashguard.
View attachment 916383
Besides, I don't buy the stability argument, the tank is going nowhere attached with 2 straps to a donut style wing and for sure it doesn't wiggle against it.
Only benefit I see is with the Apeks WTX-D30 or other wings of that design that are narrow and with deep middle section for the tank. The STA pushes out the tank a bit and makes attaching the fattest 12 and 15l steel tanks easier.