I rode Nashbar's double-butted aluminum touring frame on a credit card tour from San Francisco to Los Angeles. Using high-volume (700x32 or larger) tires tame the harsh ride that aluminum racing frames are known for. The aluminum frame worked extremely well and I wouldn't hesitate to use it again. Not being familiar with the Trek FX, the one thing I will suggest is installing your racks and luggage and doing some test-rides well in advance of your tour. I initially thought I was going to do the SF->LA ride using my normal road bike, but didn't like the way it handled when my gear was mounted...
Last edited by sstorkel; 07-09-12 at 07:40 PM.