The felt vs. Aquastealth debate is kind of like the old short rod vs. long rod debate: the only honest answer, I think, is "it depends."
For my fishing in the Southern Appalachia's, my pair of Simms Guides with studded Aquastealth were ideal: I spent most of my time scrambling on the bank and made a concerted effort to stay out of the water. Any problems I had were caused more by the studs than the rubber soles: flat, dry rocks are not your friends.
That said, I think if you're wading across the proverbial "snot-covered bowling balls" a pair of high-quality felts would be safer if your feet are always "pitched" at an angle. In fact, the Jewish mom in me would say the best solution for that
substrate would be to buy one of the nifty new switch rods and to learn how to spey cast.
Then again, I'm middle-aged, and I've noticed that the ground is remarkably harder than it was a few decades ago ...