I like refurbished SFF, I've used them for years.  When my wife's (refurbished) PC died after being used for 6+ years, I got her another one.  After about a week, it died, probably a HDD error.  So I returned it and ordered another, same as before, I figured another one would be OK.  After about a week, it died too; again, HDD error.  So no more HP's and Circuit-Tech, the boards just fine, but the cheap drives they use are crap.