I love powerstretch for the warmth factor in winter, powerstretch tights are pretty much the only extra item of clothing I cart along (besides my normal insulation), since I find it so warm, it really helps me push my sleep system along with my jacket. However, after my recent trip to Peru, where I was pretty much wearing the same clothing the whole time (I had 2 outfits total, but one of them was light jeans and a blend shirt), on and off of trail and in and out of towns, I've since sworn off synthetics entirely.
I don't have a problem with smell normally at all, I've never needed deodorant, and don't use it. 10 minutes after donning powerstretch tights or the synthetic 3/4 Mountain Hardwear running tights I've recently come to love, they start smelling, and not insignificantly, it's as if they amplified the smells.
Also, the MH wicked lite T, the MH 3/4 tights, and the Patagonia Traverse pants I had, all took for freaking ever to dry in a hostel room after a sink wash. Maybe they dry real fast under body heat but not hanging. The Powerstretch however did dry extremely fast (also MH).
The flip side to all that mess however, my LW smart wool LS zip T would dry out in an hour hanging (I only washed it twice right after I got there), and the last stretch without washing I used for days on the trail, and over a week in and out of towns and night clubs, every day, and never smelled more than stale.
However, my 200wt Icebreaker LS seems to take a fair bit longer to dry, it's got a noticeably different weave though.
Regardless, I'm replacing all my synthetics with natural fiber where possible, I can't stand the synth funk, and honestly, I don't think the stuff dries as fast as people claim.
Sorry, I know this is a digression of the OP.