I'm simply asking this because I never saw any complaints before but I played Super Mario Bros. 3 on NES Classic and it handled like shit.  I go home and play Super Mario Bros. 1 on my Wii U (Wii VC) and it handles like a pro.  I think the NES Classic games are off on control wise which completely ruins Mario since Mario is all about control.  I almost feel bad for any kid that tries Classic before the real deal.  They probably like why does Mario handle like shit?  Needless to say I traded my NES Classic to a friend and took a loss after one night with it.

Your probably sensitive to input lag.
The NES classic has less (than retropie) but more than Actual NES hardware does.

Your TV can also cause input lag, so if you have a combination of a tv with high input lag, and are useing the nes classic, the two of them together, might make for a "this doesnt feel right" experiance when playing mario.

Yea, must have been input lag. I'll let my friend know to change settings on his TV (make sure it is game mode) and maybe mess around with the 3 different mode settings on the NES Classic. I suppose I should have debugged it more but I was highly disappointment that night. Hopefully he can get it running where it actually feels right. I guess I'm good on any future retro systems. Got burned twice now. One with that shit atgames Genesis console and now NES Classic.