Took it from 7th grade to 12th and a semester in college. Spent a month struggling in Spain, but was pretty proud at the end of that time to be able to eavesdrop on local conversation (as opposed to understanding because someone is simplifying their speech for my benefit) and even pick out foreigners by their accent. Had a couple of awkward moments pissing off patriotic provincials who spoke a dialect other than Castellano, and the more you apologize and try to explain you don't know their dialect, in the offending Castellano, the angrier they get.
Some sensitive muthafuckers in Valencia!
Damn rusty now though. That was almost 15 years ago. I'd be more or less ok going from Spanish to English, but any translation I attempt going the other way would probably be akin to the Chinglish we find so amusing. The El Salvadorian guy I work with screwed up his face one day and said, "Ju sound like you from espain, man." Apparently I sound like the Spanish equivalent of a snobby Oxfordshire blue-blood.