I do both, actually. All I have right now to act as a dremel is a PediPaws, and really, for my huge GSDs and Great Dane, it's not a real good tool, but I usually clip the nails with the clippers, then take the PediPaws after and file off the nails, so I don't get the ragged broken nails scratching me after.
Bella hates the clippers, but I've been working hard on it with her, and tonight while I was doing her nails, we had a break through. She was still shaking, and nervous, and hated it, but she just sat there and let me do them. She got lots of treats and verbal praise while I did them. And now they're nice and smooth after being done with the PediPaws.