got a mate with 2:76 set up in a 70 charger. He's got a pretty tough motor - full solid roller setup, revs to 6500rpm, but the car still feels like a slug with that final gear ratio. I had 3:55's in my runner, and when he took it for a spin, he couldnt believe how much quicker mine would get to the redline than his (hydraulic flat tappet setup for me).
I recently swapped them out for 4:10's and I love em. That being said, it is getting difficult to leave anybody's house without leaving the old 2 line signature.