This answer goes with just about every place a person would musky fish. If your planning on throwing baits all day you will be very unhappy with a spinning set up.
Casting reels are in almost every situation the best way to go. With todays reels the excuse of "to many backlashes" is no longer valid, it is now almost seen as lazy to use that excuse. The advantages of casting so far outweigh spinning, I encourage when buying new gear to look at only casting if buying strickly for musky fishing with artifical baits.
If your fishing with live bait, then a spinning setup will do just fine. Be sure to have good strong braided line 30lb absolute min. 50+lb line is better IMO, a good quality leader and quick strike rig to reduce deeply hooked fish that have a low rate of suvivoral.
A big challange for people to enter the sport of musky fishing is the cost of good quality gear, for a good casting set up on a budget your looking at about $250. Yes you can fish with lesser priced equiptment but at sometime when fishing you will find that it would have been ahead of the game to buy quality once than lesser quality twice