Assuming the mounting points are in sensible places you can't beat SKS full length guards. If you want to keep your feet dry and bike clean these are what you want. However, they're a major pain to put on / pull off!
Raceblades are nowhere near as effective at keeping the mud off the bike but they will keep most of it off you. They're relatively easy to pull on / off.
MTB guards don't even attempt to keep the mud off the bike and they're not brilliant at keeping it off you. However, they wont get clogged and it takes all of 5 seconds to pull them on /off.