Mine is dying right now and needs replacing. Despite that most people don't appear to have had trouble with them and they are very quiet. Trouble is i bought mine from xcase and their rma procedure looks iffy - just send it to them with a filled in form that you print off their site, no rma number or anything like that.
It does appear that seasonic returns are handled by the site you purchased them from rather than direct with the manufacturer so whilst i'd still recommend this psu, get it from a site which you trust for returns.