Your favorite rear end/final drive ratio and why?

Probably a little late, but.....
If I were the O.P., I'd consider an overdrive five speed, and retain the 4.10s
I understand that is a mega-dollar solution, but I feel it is the best one.
For a gear change, I would probably go with 3.23, but 3.55 is a more compromise gear, the 3.23 are for more of a long freeway cruse situation.
As far as MY personal choice, I have 4.10s in my road runner, 3.91s in my 440 62, and I just bought a blackfriday deal on an aluminum center for my nine inch, with 4.10s and a spool. Very tall tires used with the new gears however. (to use in my Opel GT.)