This is far to geeky for me. Probably far to geeky for any of the reviewers and even the author. I took one look at the top right panel and that was enough. Yes I know my weight, but who knows their rolling resistance even after reading the attached notes. Who knows there drag coefficient, and area as independent figures, If at all. I think it's trying to hard. All I want to tell it is my weight and sitting position. I believe justins presumes your tucking in, as I have to if I wish to match his results. Just a choice between sports or upright would be a nice addition. This is really to much for most people outside of professional race teams