i was doing time attack in MC1 and used both Wii U VC and SNES Classic to see if any of them provided an advantage and, while my own times didn't see any difference, i did notice something weird.
it seems that the SNES Classic's F-Zero emulation runs slightly faster than Wii U VC's emulation. while this doesn't really cause a problem for the ladder, it does pose a problem for people using RTA timing for all cup runs. the time gain can be significant since i noticed a difference of 9 frames after only 2 minutes of gameplay.
i took some screenshots of this:
the above show how the Wii U VC fell behind after 334 frames.
here's the difference after more time:
the difference gets bigger over time. these 2 videos had a MC1 time that was identical once the run was over but, as you can see, the SNES Classic reaches the end slightly faster which puts anyone using Wii U VC at a disadvantage.
i also noticed the timer is slower than RTA but i think that's known already.
i think it'd be worth it to do more testing. for one, i didn't play on a SNES or on Wii VC to see how much those versions differed. next goal would be to see which one is closer to a real SNES.