I have a Trek OCLV in a size 56, and I am two inches shorter than you. I wish I had bought the size 58. And, if I were as tall as you, I'd buy the size 60.
The ideal size depends on a lot of factors other than leg length. Your riding style, your riding goals, your age, and other factors are also important.
If I were age 20, and buying a bike for riding short crits, or short time trials, the lower position of a size 56 would be ideal. But, for long rides in heavy city traffic, I want my head up where I can keep a close eye on the SUV on my left, and the pickup truck on my right, and a size 58 would make that position easier to attain.
In your case, if you are buying the bike strictly for racing, and will be in short races on closed courses, a size 58 will probably work. If you are not intending to get a racing license, and will be riding on public roads that have a lot of traffic, you probably should be looking at the size 60.
But, I'm sure that the customer service experts at BikesDirect have already spent a great deal of discussing these factors with you...just like the time spent by the staff at the three neighborhood stores where you got "free" fittings, by pretending you were interested in buying an expensive road bike from them.
Why is it that most folks who post to brag about buying from BikesDirect are "brand new" Forum members, and why do most of them seem to have the ethics and morals of a Louisiana politician?