The 3 bikes are certainly close enough to be a coin flip, but the Truvativ crankset and Velociraptor tires tip it to the Motobecane for me. Also the frame description says 6061 AL and although I'm sure the other frames are comparable, I like seeing it spelled out, so to speak.

BTW, I agree with kenhill's point about (not) using the LBS for fitting purposes only. My inclination would be to go ahead and do it, but plan on buying at least some of your upgrades and accessories from them - in that case I would have no problem with it.