Those KingSpec SSDs on eBay are pretty cheap and nasty - I'd be worried about their reliability, especially in a computer that you use a lot. You'd probably find a fast 7200RPM drive to perform close to it. I wouldn't buy any SSD these days apart from Intel or maybe Samsung due to reliability concerns with other manufacturers.

If they were < $75c/GB I'd consider picking up a KingSpec IDE SSD to try one out myself, but they're very expensive for what they are, as a generic brand with no proven track record of reliability.