We hit FI at our regular level of spending in 2013. I wanted to about double that for a FIRE budget, due to wanting kids + planning to travel full time, so we kept working for a higher FIRE income. So it's debatable, I suppose, if we really were FI--we weren't FI based on our ER budget, but we were FI if we wanted to keep the same life/lifestyle (which we were happy with, but wanted to do other things in FIRE).
Set an ER date of June 2016 or June 2017 (it fluctuated). Pulled the trigger 1-2 years early (June 2015) just because we wanted to. Basically didn't know if we were financially ready, but we were mentally ready, so we decided to give it a shot, and let the finances work themselves out. So far, so good.