My vote is for Ti
I suggest that you also look into
Serotta for a really nice custom frame.
I put 2-3K mi. a yr. on mine, coming off a 20yr love affair w/ steel. My brother is far more serious, we swap bikes occasionally. I find that his Carbon frame(Lemond) is plenty stiff but also plenty uncomfortable, no thanks. For racing and hills I am sure it's the best but if you put on a lot of milage Ti is the best.