Cannondale is way better value-wise than both Trek and Specialized.
Trek 2.1: 105, r600 crank, tektro brakes, alu steerer fork, heavy mediocre alu frame $1370
Specialized Allez Apex: apex, lowest end SRAM crank-set(square taper lol), ~1400 gram frame, tektro brakes, alu tapered steerer fork (600grams lol) $1450
Cannondale CAAD 10-5: 105, most advanced ALU frame around, ~1200 grams, 390 gram full carbon tapered fork, BB30 tektro brakes, fsa gossamer crank $1500 (also around 600-800 grams lighter than the ones above)

Now, regarding the CAAD IMO the value is at the ~1800 price 10-4 with Rival, which gives you a Force carbon crank and SRAM brakes(probably apex?). Of course, this bumps you into entry level carbon but those are all crap really.