I'll second Dean51. Nuts make setting the chain slack properly child's play. QRs can be really frustrating, esp if there anre any defects on the flats of the dropout that want to position the axle. A few late night or just "bad day" flats and you may wish you spent the extra time or money to get a nutted axle.

(A neat little trick if your frame had fender eyes: make a chain peg using a FH screw threaded into the eye from the wheel side, locked in place with one nut. The screw can be quite close to the chain and cog since nothing is ever getting out of line there. This is a promise you can never make with a derailleur setup. If you carry a Pedros Trixie wrench and have that peg, you never have to touch the chain.)

Ben