I have the trail loop, and its reminiscent of the sport loop from my AW Series 4. it is comfortable, slightly stretchy, and easy to put on. The only noticeable issue with the grayish-greenish one is that the orange pull tab gets dirty (because it is almost on the underside of my wrist).
I also bought a third-party ocean band and alpine loop (nato-looking as you say) from ebay & amazon. I thought the alpine loop was going to be a pain to latch, since it kind of slides into a loop, but it actually was easy and stays put without issues. The only bit of caution about the alpine loop latch is that is metal and on the underside of your wrist. So, it is in a position to scratch whatever is under your wrist.
