IMO call either place via telephone. Give your money to whichever one seems to have the better customer service.
Between the two, I know for a fact WOD has an extensive history of experience installing Winter shifters in Jeeps and rockbouncers. So that would cause me to lean more in their favor. If you have any installation issues after purchase, calling them and explaining it may lead to having your problem resolved by telephone.
Also, WOD has a cool shifter knob that they build for the Winter shifters. They also sell an identical set of knobs for popular transfer cases. Silly, but after install, all your knobs will be uniform and match. A tiny detail that will matter to very few.
Does PolyPerformance have a shop that they use to build stuff? They may, so they may have the same, if not more experience with Winter shifters.