Both my GTO and my 'Bird presetly run 3.55 gears. I will change the gears in my Bird for higher (numerical) gears when I install my T-56 (with the over drive.) I used to run 3.23s in the GTO. When I changed to 3.55s, the small change was very noticeable.
I love the 3.55's. At 80 MPH on the freeway, I am running just under 4000 RPM. I don't know how you feel about it, but I really LOVE the sound of my 455 at 4 grand. As for wearing out faster, how many of us do you think are going to put even 20,000 miles on our cars from here on out? In my very biased opinion, if you can keep the gears between 3.42 and 3.60, you will be very, very happy.
3.73 would be the absolute highest I would go without an overdrive for a daily driver/cruising car.
