I went for an hour walk in the MBTs and boy are my legs tired. I don't usually stretch before my morning walks but these shoes are teaching me otherwise. My calves which start tight and warm up after about 15 mins were burning the whole time. I had to stop every once in a while and stretch.
The MBT site does warn you that you have to build up your wear time over a couple of weeks and I'm sure I pushed it. I could feel my whole leg working (even the inner thighs and my weak right Achilles heel). There was still no pain in my left foot and they were still comfortable even if they wore me out.
I also tried them on the elliptical machine yesterday and they better than my regular shoes for that as well.
Here are the pairs I purchased.
