High RPM Measurement -101 or Uno-

Hello there
I'm looking for a microcontroller to read 4 high RPM's via 4 photo-interrupter at the same time. I find myself wondering if the Uno would be fast enough for the jop or if I should get an 101. I hope somebody can help me.
-theWholocker-

I noticed a post for a CDI project in one of the other sections maybe try find that and see what they are using as they were talking about RPM and all that good stuff.

EDIT its HERE

There are some more if you search