I am a keen pianist, and recently did my grade 6 exam after 4 years without lessons. It was a real challenge for sure, as I'd just been playing freestyle - jazz, rock, theme... whatever piqued my interest. Anyway, I ended up passing the exam (with distinction :p) and am now working towards grade 8 at the end of the year... The thing is, grades don't mean much to me (it's more of a qualification thing) and I never judge a musician by what grade they are. Just listen to this piece of music, an interpretation of the 'Castlevania III' theme from Nintendo. It reminds me how much I still have to learn.
Now I'm starting to learn it with an actual tutor, who notes the metaphors and implications of each note separately... which is why it's taking a long time to learn :)