Maniacs, but only with position on them. Station_Master's point about seating is the key variable here - a maniac to your left is a nightmare because they act after you and can blow the pot up once you've already committed, but a maniac to your right basically pays you off every time you wake up with a real hand since you get to see what they do first. Nits are just a low-variance grind; you know their range is always strong so there's no creativity required, you're just waiting them out and stealing blinds. Maniacs at least give you the chance to win a monster pot off one good read, even if the swings are rougher.