I am trying to decide if I should pick up a second GTX 570, or wait another year and replace it with a new gen model. I have been looking at benchmarks, and in most games it scales very well (80-90% in a lot of cases). I am not having frame rate issues or anything, I am just trying to ensure that in a year or two I will still be able to run new games on high-ultra settings at 1080p. At the moment, the cheapest GTX 570 I can find is a MSI TF2 for $230, which is not terribly expensive. I built my rig fully capable of adding a second 570, so all I need to decide is if it is worth it or not. Add a second 570 for around $250, or wait a year and buy a new one for $400? Also, as I have never ran SLI before, is there anything I should be aware of in running two different brands of gpu? MSI Twin Frozr 2 vs 3 for example, or another brand name entirely? I assume the TF3 will clock down to the TF2 on default, and then I can OC them both together if I want to?