A lot depends on your personal taste in shoes. And I don't have any experience with the TechAmphibian2, but I regularly used to run long distances off-road in the first-generation TechAmphibians. In fact, I won two trail marathons wearing them! As long as you're not looking for masses of support/motion-control/protection from the shoe, I would definitely give them a shot. One point worth considering: the old TA's seemed to be sized for use without socks. Either wear a very thin sock, or buy a half-size larger than normal.

I'm assuming that you are doing some sort of adventure race and I definitely would not use these shoes for that. Go with one of Salomon's trail running shoes with the quick tie laces. Stay away from the GoreTex since once the water goes over the top you are screwed, so you'll want quick drying. Salomon has a few styles to choose from, so see what matches your budget and your foot the best.

i wouldn't feel comfortable doing it in mine. I would use goretex salomons with the neoprene ankle gaiter.