SLI is super annoying. Microstuttering (even though you have a high framerate, it's never smooth), games that don't support it, games that perform worse with it turned on (ask Shaneus), high power usage. You'd be better off just buying a new video card in 2-3 years imo.After looking at SLI benches the 670 scales really well, so I might grab another in a year or so.