A little update on this power meter. Loving it so far. A couple of things I have found. They released an update in July that makes it accurate on rough surfaces, like gravel and trails. It can measure rolling resistance. Another is I ordered the Lite, which is supposed to have only one bike profile and no PowerStroke with limited Isaac software, and the Isaac software I finally downloaded tells me I have it all. Yippee, free upgrade! It also has CdA analysis for all those TT and Tri people out there, and cheaper than the AeroPod. PowerStroke is pretty cool. It basically told me I pedal squares yesterday, lost 3 watts to it, and rocked the bike a side to side a bit while pedaling.