Adrian, MI
I went with MB, although I like LOTR too. I always like the Universal Monsters, ever since I used to watch Abott and Costello re-runs in the 70's LOL. The art, sound, and humor are also big factors for me. Plus it's pretty much immediately accessible, as in you can get to Monsters of Rock within minutes, so you don't have to play for 30 plus minutes to get somewhere. That may be a negative if you like real deep rulesets like on LOTR.
MB is just plain ol' fun, but may be too simple and considered easy for some. As said previously, pretty much polar opposites for difficulty and/or depth of rules.
