Re: How long did it take you?
1) About six years. Looks to be around average from the poll.
2) It varied, but after I got my driver's license I was going to around 6 or 7 classes a week.
3) Yeah, I had to take two months off after some jaw surgery shortly before my second kyu test. The oral surgeon and my parents wouldn't listen to my arguments about how aikido really isn't a full contact sport. I ended up taking more time off after shodan but that's another story.
4) My Sensei said I did. I sure worked for it.