If case it helps anyone... My wrist is 165mm, for reference. I've now had each of the Ultra bands. Here's my personal opinions on them. Your opinions could be very different, depending on how you use your Ultra, how you dress, your preferences for different band types, and a lot of other individual preferences. As a spoiler, the one I liked best by a big margin was the Trail Loop.
Alpine Loop (Green M)
Things I liked: Dried pretty quickly after workouts. The titanium hardware is Art, at least in metalworking terms: beautifully shaped, exquisitely made and functionally indestructible.
Things I disliked: Sort of fiddly to get on and off. Pulling it tight was a little awkward because the loops catch on the hardware so I sometimes felt like I had to pull it tighter than would be comfortable to get it right. Getting the clip into the loops was a little awkward. When you take it off, you need to exercise a little care to avoid smacking the case and/or display with the clip. I wonder if the clip will eventually fray or cut the loop that it's usually/always clipped into.
Subjective score: 4.5/10
Ocean Band (Midnight)
Things I liked: Surprisingly comfortable. Better airflow than I expected, probably because of the figure-8 profile. Easier to get a comfortable but snug fit than I expected because the material stretches a little. Easy to customize the placement of the keeper. The midnight blue is very attractive (opinion). If you like the look and the bulk and "stickiness" aren't issues, this is a great strap.
Things I disliked: Nearly everything I wore that had long sleeves would catch on the strap because it's a little "sticky" (not quite the right word).
Subjective score: 7/10
Trail Loop: (Black S/M and M/L)
Things I liked: Infinitely adjustable, and very easy and quick to get a comfortable but snug fit. Very breathable. Dries quickly after workouts. I like the way the black with orange pull tag looks (opinion). I'd repeat the comments on the hardware made about the Alpine Loop. I don't know if the hardware is worth a $50 (100%) upcharge compared to the Sport Loops, but it's very reassuring to look at the titanium hardware on the Trail Loop. I don't get the same feeling looking at the molded plastic ends on the Sport Loops.
Things I disliked: Nothing, but read the sizing note below. None of the Apple stores in this area have any Trail Loops to try on for sizing, and none of them can do a return/exchange involving only a watch band, so getting the right size may require returning a watch/band set, which could be annoying and is definitely wasteful.
Subjective score: 9/10
Sizing note: Unexpected issue on sizing. I ordered the S/M Trail Loop based on the sizing information. While technically a very good fit once I got it on my wrist, it was very difficult to get it on and off. Maybe my thumbs are disproportionately large. Both thumbs have fairly significant arthritic pain, so maybe that's part of the problem for me - YMMV. In any case, getting the S/M loop on and off was difficult enough that I ended up returning the S/M for the M/L Trail Loop. The M/L isn't too big and is a lot more comfortable to put on and take off. Interestingly, the M/L Trail Loop opens up to a slightly smaller size than the Sport Loops because of the pull tab. I would guess that most people who are satisfied with the way the Sport Loops fit should order the M/L Trail Loop, not the S/M.
Alpine Loop (Green M)
Things I liked: Dried pretty quickly after workouts. The titanium hardware is Art, at least in metalworking terms: beautifully shaped, exquisitely made and functionally indestructible.
Things I disliked: Sort of fiddly to get on and off. Pulling it tight was a little awkward because the loops catch on the hardware so I sometimes felt like I had to pull it tighter than would be comfortable to get it right. Getting the clip into the loops was a little awkward. When you take it off, you need to exercise a little care to avoid smacking the case and/or display with the clip. I wonder if the clip will eventually fray or cut the loop that it's usually/always clipped into.
Subjective score: 4.5/10
Ocean Band (Midnight)
Things I liked: Surprisingly comfortable. Better airflow than I expected, probably because of the figure-8 profile. Easier to get a comfortable but snug fit than I expected because the material stretches a little. Easy to customize the placement of the keeper. The midnight blue is very attractive (opinion). If you like the look and the bulk and "stickiness" aren't issues, this is a great strap.
Things I disliked: Nearly everything I wore that had long sleeves would catch on the strap because it's a little "sticky" (not quite the right word).
Subjective score: 7/10
Trail Loop: (Black S/M and M/L)
Things I liked: Infinitely adjustable, and very easy and quick to get a comfortable but snug fit. Very breathable. Dries quickly after workouts. I like the way the black with orange pull tag looks (opinion). I'd repeat the comments on the hardware made about the Alpine Loop. I don't know if the hardware is worth a $50 (100%) upcharge compared to the Sport Loops, but it's very reassuring to look at the titanium hardware on the Trail Loop. I don't get the same feeling looking at the molded plastic ends on the Sport Loops.
Things I disliked: Nothing, but read the sizing note below. None of the Apple stores in this area have any Trail Loops to try on for sizing, and none of them can do a return/exchange involving only a watch band, so getting the right size may require returning a watch/band set, which could be annoying and is definitely wasteful.
Subjective score: 9/10
Sizing note: Unexpected issue on sizing. I ordered the S/M Trail Loop based on the sizing information. While technically a very good fit once I got it on my wrist, it was very difficult to get it on and off. Maybe my thumbs are disproportionately large. Both thumbs have fairly significant arthritic pain, so maybe that's part of the problem for me - YMMV. In any case, getting the S/M loop on and off was difficult enough that I ended up returning the S/M for the M/L Trail Loop. The M/L isn't too big and is a lot more comfortable to put on and take off. Interestingly, the M/L Trail Loop opens up to a slightly smaller size than the Sport Loops because of the pull tab. I would guess that most people who are satisfied with the way the Sport Loops fit should order the M/L Trail Loop, not the S/M.