I thought about this, and saw some of the cool demonstration video's on youtube but when i held the saris mag unit it place and spun the rear drum i didn't get any increased resistance, however i could have dismissed this to early.

I'll do a full boar 20 min riding experiment today, one with my tacx mag unit, one with no mag unit (control) and one with the saris unit adjusted per the manufacturer's instructions on each level of resistance to see if it is compatible with nashbar rollers. I'll plead guilty, i simply thought regardless of Farraday's law, the drum walls were just to thin to be affected, and i thought for sure, a manufacturer would alter their rollers slightly so that their mag unit would only work with their rollers. But i forgot about the "faster it goes more resistance"-part, so i'll try and report back by tonight.

Yay! experiment!