I didn't really think about the "spring back" portion of Schrader valves, but yes that makes sense. Again, I'd suspect the Schrader valves would gum up quicker too, but having not used them I can not comment on that for sure.
Trying to reply to your below comment, but can't for some reason? I'm new... sorry!
As for the below re: Presta being better high pressure applications. This was something pointed out to me only last year at a week of suspension tech/wheel building at UBI. Almost EVERYONE has the conception that presta holds air better, and is better for high pressure applications. But, your rear shock seems to have no problems holding up to 300 PSI worth of air in it, and it's got the handy 'ole Schrader valve going on ;)
Realistically presta valves were created so we could drill smaller holes in rims so we could better experiment with rim shapes/profiles. I would surmise at this point we could potentially move back to schrader drilling with the wider and wider rims we keep seeing, but I would suspect they would clog up easier? All speculation on my part!
Off the top of my head I can't remember my exact inseam in mm, but the ole legs are too short for 32" inseam pants, but slightly too long for the 30". So, just above 30"? Lol. I'm running a direct mount round chainring (they are Hope cranks, for the record)
Made the switch to shorter after some fitting work. After doing some other fittings, it would seem most people would benefit from shorter cranks. The smaller circle you pedal is easier on the knees (which is especially helpful for many who have had knee surgeries; not me) and typically cuts down DRAMATICALLY on hip rocking while pedalling.
I did not at the time think to try any of these other options. I was so disheartened at the time, I just immediately switched back to 29+ so I could continue riding the bike I was enjoying :P.
I'm think that said low BB height had something to do with it's "off" feeling. I didn't run into any pedal strike issues, though, I'm running 165 cranks (not so much for pedal strikes, but a better fit for me).
I've also got myself a Stache 7 that I'm currently loving (I added some quite worthy upgrades though... whoops). I got my hands on a set of Bontrager's Chupacabra tires in a 27.5" size, slapped them on some 27.5" wheels and mounted them into the Stache.
I was not nearly as enamoured with this setup as I am with the 29+ style. Maybe I need a lower Axle to Crown height fork? Maybe I needed to make some other changes? I'm not entirely sure, but I can say that somehow the 29+ setup felt more playful than the 27.5+ setup I tried on the Stache.
Obviously, this doesn't quite apply to bikes like the Primer that have the ability to run 29" and 27.5+ wheels. Have heard good things about that from friends I know with Trek Fuel EX's that can run both.
Anyways. Those are my two cents on the 27.5+ debate SPECIFICALLY for the Stache.
I've somehow managed to double post... I just wanted to reply to LWK. :(