As I understand it, the more addons you have, the longer it takes. After a box restart, mine takes about 30 seconds, then after that it's more like 10-15. including the box-stock planes, I only(?) have 101 aircraft folders. I remember when I once had to reinstall FS9 on my old XP rig that the stock install actually started up pretty quick, but then when I dumped in my entire hangar from multiple CD's, it took a couple of minutes. But again, it took much less time to start up after the first time. My guess is there's something cached somewhere that speeds things up, but I'm not sure where that is.