So, I'm really curious what everyone else's experience with this strap is, because mine wasn't great. Despite nmankey's insistence that the strap won't stretch (or at least not by much), mine most certainly did, and by a lot. I wore it on a Seiko SSC425P1 (20mm lug width) and it's a fantastic match, aesthetically, but after only after 1 month of wearing on a non-daily basis (3 or 4 days a week) the strap had stretch by more than half an inch! See below:
You can on the left-hand side one area that didn't seem to stretch very much and it's still pretty close to accurate (i.e. 1" strap = 1" ruler). However, look on the right-hand side and you can see that the strap, as a whole, has stretched by more than half an inch (9" strap = 9.5" ruler), and that's without flatting it down where it ran through bars (that makes it an extra 1/8" longer). And this is after not wearing it for the last couple months.
I wore it using both studs in order to try to distribute the stress, and I wore it just snug--not tight like I see some of the images from other posters where the band is visibly squeezing down on the wrist, since I find that to be uncomfortable during long days on a keyboard. And yet after only the first week it had stretched enough that I had to move the stud. The next week, out of caution to the stretching issue, I wore it loose enough that I could get a good around 120 degrees of rotation around my wrist (so, fairly loose), and yet by the end of that second week it was again lose enough that I had to move both the studs and switch to different set of holes. One more week of similar looseness (because hey, how much more could it possibly stretch, right?) and again, needed to move the studs. I gave up after this point because the strap was beyond accurate (not that this was a real selling point, but still) and because I could visually see the warping/narrowing of the leather around the studs and holes. Also, the anodization on the "black" studs is mostly warn away (especially in the inner one, which you can see in the image above).
I should note that I was careful not to get it wet or do anything that could compromise the leather; at most it got an occasional splash while washing my hands. I didn't get exceptionally sweaty while wearing, either. And the watch isn't particularly heavy. So, really, it just stretched like crazy during totally normal wear. Maybe a 22mm width would hold up a little better, but this 20mm absolutely did not. Pretty disappointed, frankly, but I guess that's the risk one takes; definitely glad I didn't pay MSRP!