I found that the Openelec build I was using caused issues with the database and image cache when after my power tripped a few times, and that caused serious hassles with Openelec being my main HTPC. Required a fresh installation each time to get it sorted, otherwise the menus would be slow and playback could take up to 20 seconds to actually start. Haven't had the same issues on Windows and if I did, reinstalling is far easier as well, as is backing up the database. XBMC has an automated database backup feature but it doesn't delete the previous backup, so you end up with a 20gig folder of backups.
Must admit, I'm far happier on Windows than Openelec, even though I mostly enjoyed my Openelec experience. The nail in Openelec's coffin for me was when the Supersport plugin stopped working and live streaming required a browser...