My vibrations are almost all confined to the 1000-1200 range, other than that the car is just a little more throaty than before. On cold start driving in in-town traffic this is still a little annoying since my idle stays up there until the car warms up. And in stop and go situations, there's vibration every time as I rev up from idle and again when I drop down into idle.
There's no real reason to drive in the sub 2000 rpm range, that's where the engine starts to lug and you lose mpg and hp; downshift to keep the revs up, which means this mod is actually helping remind you to drive better.