I'm getting a rush and I have been trying to figure out what the perfect size is for me. I was wondering if any of you who have experience with the frame can give me some advice. I'd either get the 55 or 57, the 55 has a 55 top tube and the 57 has a 56 top tube. (the 55 and 57 is measured c-t for the seat tube). I have ridden a 55 with a 100mm stem and it felt ok, possibly a little small, but The thing is I'm also used to ridding a bike that is to big for me, so me conception of what is small might be off... I'm not sure.

I'm a hair under 6ft and have about a 34inch inseam. I'm leaning towards the 57 with a smaller stem, but was wondering if I would be better off with a smaller frame or not. I know I'm nitpicking but any advice would be greatly appreciated.

here's the geometry:

http://www.somafab.com/geometry03.html