I studied for the LPIC-1 about a year ago, for time reasons I had to stop. What bugged me most back then was that one hand some topics weren't asked with regard to newer development results (I'm not talking about yesterday's new kernel-near driver but about filesystem changes that have happend around five years ago.) and on the other hand they forced you to learn all sorts of really exotic flags for commands that you use around once in a lifetime and normally just look up in the manpages. Luckily at least the thing about old stuff in the questions has changed with the last revision, they also added IPv6 now which makes me especially happy.

Personally I'd prefer LPIC over RCSA or SCLP because it's not specific to any distribution (There was a separation between LPIC for Debian/Ubuntu and LPIC for Redhat some years ago, luckily it's long gone.) which is better if you don't apply for a job which explicitly requires Redhat or SuSe skills. I'd have a got for it, it's not that hard - I couldn't make it (:D) - and worth it, even if your certificate expires in five years. You should try to undergo the exam during a conference or something similar, there are mostly heavily discounted exams.