There are trade-offs for sure. Full fenders rattle, rub, and make transporting your bike a pain, as noted above. But they do keep crap from being flung from the ground onto you and your bike.
Raceblades and the like will prevent the Freshman Stripe and save your group ride comrades from a face full of mud, but they don't protect your brakes, FD, and crankset from getting covered in gritty, wet crap. Viz:
