Originally Posted by kimchijajonshim
I'm not 100% sure, but I think his concern might be what reference stance is. Without micro adjustments your options are either to go up/down 1.5" inches in stance width or 3/4" if you're willing to / want to mess with reference set-back. I would have similar concerns if I had Reflex bindings... enough that I might switch them out for Forum "good vibes" discs (which do have micro adjustment front-to-back but are hinged).
Reference on the 157 Proto and my 158 SL is 21.5". Assuming a 155 Proto has the same insert widths (not 100% sure on that, but seems reasonable), your options with a centered stance and Reflex bindings would be 20", 21.5", 23", and 24.5".
Thanks, I appritiate that.