And I'm doing it on air and I was winning with just 2 cards
Actually the GTX 285 is also using the same, memory controller/subsystem/whatever it's called, as the GTX 260. So that's also a disadvantage for the GTX 285. Plus, in my opinion, in order to justify the GTX 285 Nvidia set it's base core clock as high as possible so the numbers would say it was the faster card. But that just reduced it overclockability.
After playing around with Tri-SLI for the past few days I really don't see any reason for it. The third card doesn't scale for crap and the cards are crammed together like Sardines. It's creating way to much heat for a few more fps that I don't need anyways. I'm going back to regular SLI and this 3rd card is going in my Office PC.