XD w/ thumb safety thread, that's one thing that could go wrong, you get use to having the thumb safety off, and the one time you need to draw, the thumb safety has some how gotten engaged.
I didn't have a chance to try the different back straps. I'd have to say the biggest thing that I didn't like about it was the sights, I just don't like 3 dot configurations any more, I've been spoiled by Heinies, Novaks and Big Dots.
Again, going back to my criteria, holster selection and spare mags is limited on the SR9 as well. And as noted, it has no track record, that was what was keeping the M&P off my list, it met almost all of my criteria, after looking at the few issues Lima has had, and the number of issues others have had, those two were a no-go. Someone else can guinea pig the SR9.
After they've been around for a while, and some different sight options become available, and they make a model without the thumb safety I might try one out. If I can find a rental somewhere, I'll be sure to wring one out and see what I think of it.