According to my calipers, they measure the same at the thickest point. So technically, they are the same width.
However, the Grips stock Noryl scales are rounded, which makes the knife seem thinner in the pocket. The Wilkins maintain their thickness all the way to the edges, which makes them a bit blocky compared to the stock Griptillian handle.
I had a full size WilkinsGrip, on a Ritter blade, and it didnt seem overly fat to me. Bear in mind that I was using it as a survival/outdoor folder, not an EDC for string and envelopes.
I like thicker handles on outdoor knives because they dont dig into my hand like thinner handled folders do. Its a worthwhile tradeoff for me. And yes, I do have some very thin folders for the urban jungle, I like them too.
Although I dont have the knife anymore, I really liked the WilkinsGrips. It makes any Axis feel and look like a custom.