Hrm. Building characters can take longer, but I'm the kind of guy that damn near memorizes everything he puts his hands on, so I know pretty much all of the costs and whatnot already, and I use an Excel character sheet that does alot of math and keeps things put together straight.
Maybe it was just my group and how I run games, but we REALLY found it to go by fast. Partly because of the Mook rules, partly because even with Big Bads, once you've figured out what you need to average out a Stunned rating, or how many hits you need for an average Stunned rating ... Stunned Equals Death. After Stunned, it goes downhill rapidly. ("Stunned Equals Death!" was my players' battlecry for MnM.) Maybe it was just us, though.
--fje