Are they used? those exact same bikes? Are they both the same size/ right size? both in good working condition? which level of crosstrail? are you sure of the level of the diamond back? whats the prices if not new? They both appear similar the diamond back doesn't have a front suspension so its got less off road appeal which when you have a hybrid is good to go off road. Specialized is the more boutique brand and the years you give it is the newer one.