I'd pay about 10-20$ more for it.
But any more and you're getting close to the range of the very fast (90$-80$)
GTS 250 1gb, and 4850 512mb
Honestly, if you want a huge gaming boost, go for this:http://www.newegg.ca/Product/Produ
I would recomned just bucking up for this, very fast card.