I bought an inexpensive circle cutter to go with my dremel, and I've yet to cut anything that resembles a perfect circle with it. I don't trust it for the real deal. For my first cigar box uke, I bought a 1 inch spade bit, which worked great for the first hole, but on the second it snagged and tore out a half inch close to the edge. Fortunately it glued back in smoothly, and then I used the dremel hole cutting tool to make the hole bigger, albeit, still not round, and then I used the dremel and a sanding drum to make it better--actually looks pretty good. I was considering the stewmac Soundhole/Rosette Routing Jig, but you also have to buy the routing base, bringing the cost to $100+. I googled the subject and found a page that said to use a small circular saw. That made me laugh--not that it isn't possible, but it certainly wouldn't be the first route I'd choose.