Hi Steve,
Last season I bought a new pair of the hip-high NEOS River Trekkers and used them for 10+ days in Alaska. I had exactly no problems with them the entire time. I only used them when I had to actually wade a river, and I never wore them while hunting or 'trekking'. Here are my thoughts:
Very strong and sturdy.
The aggressive sole makes for good traction on rocks.
Extremely leak resistant due to heavy cordura and strong stitching.
I didn't like the hip straps, so I made my own and stitched them to the waders.
Easy to wade in, and gave me no trouble on crossings.
Heavy. For me, just too much weight to carry in my day pack. Fairly bulky, too.
I do recommend them, but I guy needs to know they are not perfect. For a float hunt they might be outstanding. For a carry and use-as-needed wader, they are bulky and heavy at 3-4 pounds. That makes them much lighter than rubber hippers however, and you can still wear your preferred boots when away from water. Donning and removing any wader like these is a bit of a hassle, so know that going in.