I haven't had the "honor" of using a dremel yet but I can tell you hole saws are pretty easy for blowhole cutting. I just finished a 120mm intake fan with a hole saw. If you have access to drill press its a walk in the park. Luckily my Dads a carpenter and has every tool under the sun (except a dremel) and we had a 120mm cut in about 15 minutes. Only advice: prep well, know exactly what you want to do and where - DON'T WING IT, Drill pilot holes. If your using a hand-held drill with a hole saw they have a tendency to go skipping off leaving big unsightly scratches on your case. take a small drill bit and drill a hole right where you want the center to be, then switch to your hole saw and let loose. Clamps are your friend... 3 guys can't hold something as efficently as a good clamp or two, reason: the clamps never have to sneaze or scratch. Just my 2 cents. I plan on doing some fancy cutting on my side panel pretty soon with a jig saw. Should be fun. If you have a friend whos a carpenter buy him a pack of <non-alcoholic beverage> and goto work. And remember: Don't Drink and Mod. (this is serious, powertools and drunks DON'T MIX)