The main problem I had in formal learning of Japanese is the fact that it’s that, ‘formal’. Meaning that I was being taught ‘high forms’ which just got me funny looks when I talked to regular Japanese people. Sort of like being taught to speak the ‘Queen’s English’ while everyone around you speaks with a Southern drawl. I guess it really depends if your focus will be to understand the language or converse freely with it.
And finding other people to practice with is very important. Very few of my friends spoke any Japanese at all (Come to think of it, most are Hong Kong immigrants) And my mom was no help, she spoke a very corrupted ‘backcountry’ dialect of Japanese. (Corrupted meaning it was laced with Hawaiian pidgin)