I get tons of scroll lag in the app store (top charts, etc.) on iPad 3.
Also, I just got this phone to replace my lumia 920. So nice to have google maps/navigation back, and the phone feels like a feather in comparison.
That's cause the CPU in the iPad 3 wasn't enough power for the 9.7" retina display. Fixed in the iPad 4. Same with the MBPr.