well... it's the truth, whether you like the answer or not. Don't post if you aren't going to like the replies, or ignore them. Grow up a bit and stop asking questions if you already know the answers...
If you care to search, there are also many threads about this kind of thing, as well as an Excel file with many approximate gradings on it (although many are quite wrong).
Plus, it's down to the individual, and how passionate you are about learning the piece.
I was the first one to reply. Probably because the other members don't have the patience to bother replying to this type of post. They're annoying, and hardly constructive, especially when the OP has this kind of attitude.
Please, if you want to start a difficulty thread, at least make it more general so other people can benefit, rather than extremely specific to your situation.
That said, I'm probably as guilty as you when I first started posting here, and I probably got a similar response as this post. So, I apologise. But be aware.