Rebuilding the database from scratch is not that bad. A few minutes maybe, assuming that I did something bad and wiped the database files completely or I am doing a sync. Day to day boot is not long enough to really notice. Probably the nastiest bit is when it tries to fsck the drives - 45 minutes per drive, and it usually wants to do both at the same time because of the mount counter. I make certain I do this if I have no plans on using / moving it for a while.