I'll join the 2020 group as well, as a sort of general target... That'll put us both mid-40's here.
I've only been tracking expenses the last 2 years, and this is the first time I've bothered with the projected budget... I was pleasantly surprised to find that my back of the envelope calculations were too pessimistic. If we keep living our spendy pants way and lose the jobs, we're covered by the 4% WR. Cutting out the expensive hobbies puts us at about 3% WR. So, *technically* we're FI by the math, but when I look at my investments and how poorly they've recovered from the big crash, I have to question whether those historic returns might be a bit optimistic in the future.
So, I'll feel much more comfortable with a larger 'stache, and I still enjoy doing what I do now. Whether or not my employer still values my contributions, though, one can never say. :-) 2020 sounds like a reasonable timeframe to shoot for to rethink my "rest of life" plan if I can make it that far! I'll concede that it's possible I won't make it that far, only time will tell. :-)
My wife enjoys working so much that she plans on working to 65 though. We've found that she does not really like idle time the way I do. I've been off work for a few months before and loved it. She lost her job a few years back now and was bored within a week. She's just now starting to get some interviews again, the job market has been absolutely horrid these last few years. She ran out her severance, extended unemployment, and then found nothing for months before finally getting a few part-time minimum wage hours here and there. She's finally getting some nibbles now and hopes to find something full-time before the year is out. That would make me feel a lot more comfortable, being the only one carrying the responsibility for earning money for years on end gets very tiring.