I got my first pair of sticky rubber Riverwalkers last fall, and managed to blow out the seams over the summer. Durability issues aside, I was pretty pleased with them in certain environments.
There are some rivers where they’re very likely to end up sending you into the drink if you’re not careful- River X that Zach and I fish is a great example of this. On slick non-algae coated rocks they just don’t work well. I haven’t used them on any rivers with lots of moss/algae, so I can’t say how they’ll work there.
For 75% of the rivers I’ve used them in I never noticed any significant difference in traction compared to felt. The other 25% were experiences where I very much regretted wearing them.
On the plus side, at least the soles didn’t fall off of the boots like my felt riverwalkers have. I’ve also yet to find a boot as comfortable and light as the Patagonia’s, so I’ve just gotten used to replacing them every year.