I don't actually have any recommendations, as the one RideNow TPU tube that I bought hasn't yet been installed. That said, one of the ways they get the weight down is to use a plastic valve stem. No particular positive/negative views on that, just that it's different. One thing I've read about TPU is that they're better on the wheel, rather than as a spare, as the freezing CO2 temperatures could potentially crack the TPU plastic (or valve). They're much more likely to be inflated by a floor pump at home, which doesn't cause the same kind of stress.
I'm 5'10", and while I'm weight conscious when I'm selecting parts, but I'm not especially weight weenie. I was able to fluctuate between upper 170s and low 180s for a while, but any time I got too close to 170lbs, I'd invariably get sick. These days I'm floating in the mid 190s, and definitely need to lay off the pie once the holidays are done.
I'd be happy to be able to hold 170-175!