So I've been using my SLI GTX465 for a little while and I'm very satisfied. But it's time to upgrade again. I was looking for another SLI set up. This time I'm actually considering ATI Cross Fire, however. But the negative input I get sometimes about the drivers and etc is quite a turn off for me considering it's really easy to set up SLI and drivers from Nvidia. I was looking into the 6950s cards which seem to be able to unlock to 6970. Is this easy to accomplish? Are there any risks? On the green side I was looking into a pair of either GTX470s or GTX560 Tis. Inputs please?