Does the V-Strap really make a difference, or is it there to just shave off some weight
I don't think Ride claims that Contrabands give better
performance than similar two-strappers -- just comparable performance. The purposes of the V-strap are to speed entry (only one ratchet to crank), improve comfort (less pressure on toes), and reduce weight.
You shouldn't need to have a shop adjust the bindings. There's a video on Ride's website that explains how to set them up. All you need is a screwdriver. It doesn't look all that different from setting up any pair of bindings. The straps are in a different configuration, but the principle is the same.