The dust is settling in the sole wars, and it looks like GripWalk is becoming the standard for the comfort version of a DIN (ISO 5355) sole. The WTR originators, Amer Group, will still offer some WTR variations over the next season, but I believe that it will abandon that ship once the stock depletes and migrate over to a sole that is compatible with a GripWalk binding, evolving all bindings to MNC (multinorm certified) and allowing all soles including ISO 9523 to work. Other than race-specific bindings, there are fewer and fewer bindings that are not at least GripWalk-compatible, and most are some of the older ones on the market.

As a skier who used a GripWalk boot during the past season, I can say they are indeed better for getting around the base of a ski area. The new articulated sole is easier for walking, and the grippier soles make a difference in traction. That said, I still believe that this design, concept evolution, or whatever you want to call it was a solution in search of a problem and that walking could have been improved (although not as significantly) with a good Vibram-type sole that would work with skiers' current, and perfectly fine, bindings.

Since your new binding choices are clearing, the discussion now happens with your bootfitter. Knowing that your current bindings might not be forward-compatible, what are you willing to give up in your current gear and what are you willing to give up in comfort and walking performance? We were in a shop this past fall observing a boot fit. The customer bought a pair of boots that had a WTR sole that could not be swapped to a DIN design and was resolved that his current groomer skis would not be compatible with his new boots. His $800 boot purchased became a $3,000 purchase as it turned into boots as well as frontside skis and new bindings for his powder skis. He was willing and able to make this financial commitment, but most skiers who need new boots won't be.

Fortunately, most of the GripWalk (or WTR) boots offered today have DIN soles available. A better shop will have these options for you and will be able to educate you on the benefits and the costs. If the sole is not backward-compatible, they should make you aware, preferably early in the fit process.

The Numbers Game: Bindings, Part 1
The Numbers Game: Bindings, Part 2