So, my local shop has told me that a Surly Cross Check can't be run as a fixed gear because the wheel can slip out of the dropout. I know Sheldon says they're fine, I know dozens of people have posted their fixed Cross Checks, and hell, even Surly says it's fine. The problem is, I like the people at the shop and would like them to build up a frame but don't really know how to handle it.
I'm about 220 lbs and we live in a very hilly area, so I thought that might be a factor. Are they full of it or are track ends necessary if a lot a stress will be put on the drive train?