Hi Dave,
RWS puts extra padding in the backpad which makes it extremely comfortable.
I wouldn't say a MUST, but personally I wouldn't like to have my next Vector without:
-Trulok toggle system
-Stainless Steel hardware
-Freefly handle (looks like pull-out, is throw out)
-Split Color option
-Custom fit (ring)harness
-Anti-twist risers
Joris. ICARUS Canopies Europe
c/ Valles s/n, El Ramassar
08520 Las Franquesas
Barcelona, SPAIN