I agree with shakran: if you can combine grappling and muay thai, then go for it. I don't know if you're into competition, but both these clubs are likely to train with that in mind. In my experience, there is a huge difference between clubs that train for competition and those that don't. I've shared mat space with aikido, hapkido and danzan, and they all seemed very staged; "you do this, I do this" kinda thing. I guess it can still be fun to learn new stuff, but I prefer techniques to be reality based rather than check-this-out-this-looks-cool based. In the worst case, the students go around with a false sense of confidence, maybe ending up getting hurt in a street fight when they should have been running.
Hunnychile, check out jet kune do if you have that where you live. There should be no zen or dark aura, but that's really up to the instructor.
Fourtyrulz: Everyone has been a newbie at some point. Go check it out
