Definitely go with Bluff Limbo. It was the first Mu-ziq release I snagged,
and still the best in my opinion. Diverse, funky, and brimming with great and
fully-developed ideas (which some of Mike P's later releases are notoriously
lacking in).
Lunatic Harness is basically In Pine Effect with breakbeats (huge
generalization, but defendable), so unless you are really into dnb, you can
skip acquiring it til later.
J