Found on slrpnk.net

This evening I got to apply one of my rules for DIY repair...
If you're looking for a replacement part, and a bunch of sites, some of whom are reputable and known to you, have it for around the same price, and you also see it listed on eBay, Amazon, and/or sites you don't recognize for like a half or a third of that price... pay the higher price. Trust me, do not buy the cheap knock-offs, you will regret it.
(Tonight it was about a laptop battery, but this rule applies in general.)