Ha, no guru mate, just like good gear that works, just ask Rene Vaz, he's sick of hearing me whinge about the shortcomings of modern gear! The G3's are very good on the rocks, they ain't no felt sole... but probably the best I've used for a while, the older Riverworks were also ok with the Vibram sole. OR you could just fish didymo infested rivers... that stuff is super-grippy to wade on!
I always run some off-the-shelf orthotics in my wading boots to help with fit as I find them pretty spacious even with a wader sock or neoprene sock, makes a HUGE difference to walking comfort IMO, but then again I have tiny wee ladies size 9 feet!
Wading boots for me, also double as tramping boots, so I make sure they work 100% and some had some boots fall apart in the upper Ngaruroro once and had to walk out with them hacked up as improvised jandal's... wasn't fun!
Andrew