When I first got on the powercranks bike, I was on for two minutes and I was biking without any coordination btw my right and left foot.  The whole time I was thinking I hope I didnt make a mistake buying these because it just feels too weird.  I kept on trying the bike throughout that first day just to see if I could get better but it took a couple of days. And it took until about a week and half to start noticibly changing my running form.  I noticed that my stomach would not get as upset post run if I ate something within an hour before the run.  I am continuing to use the cranks 3-4 times a week looking forard to my upcoming cross country season which is coming up sooner than ever.  I'm just starting to use the extension on the basic adjustible crank and everything is feeling good.  I've only rode it with the new cranks once so more results on that in my next blog.