I would recommend the faster, and less power hungry, GTS 250. Also, the extra memory is a nice bonus. Should oc very nicely as well with that nice cooler.
And ya, you do have a lot of posts
Still, getting the newest thing with these cards isnt always best, there is personal preference and situation. For instance, keep in mind, 9800 GTX's will SLI with the GTX+, but not the GTS 250. A GTX+ is both forward and backwards compatible.
So, I already had a 9800 GTX, if I wanted another for SLI i would look for a GTX+. But I diverge, you are talking about folding, not SLI.
My recomendation still stands, I dont know a whole lot about sparkle. Anyone have any experience with them?