My initial concern was scaling, and of course drivers. I wasn't sure if I would get the "bang for buck" SLi/CrossFire is meant to provide but I was very surprised. To give you a more solid representation of how the system benchmarked and scaled in SLi: Just Cause 2: 1920x1200 4xAA 16xAF + Everything Maxed [Desert Sun] - Single 560Ti: 84fps average. - Two 560Ti: 138fps average. [Concrete Jungle] - Single 560Ti: 34fps average. - Two 560Ti: 49fps average. As for driver issues? I haven't run into any issues so far with the games I play. I am not sure how that will translate to older titles but older titles don't require as much processing power and a quick push of a button disables the second GPU (without a reboot) and I can run old titles. The reason for SLi is to give you higher performance for the newer titles that demand the processing power, and as a result are usually designed with both single and multi-GPU setups in mind, be that CrossFire or SLi. Well that's a fair statement I admit. But I was looking for "power per dollar" value and currently at pair of MSI 560Ti' Twin Frozer II's run $225, whereas a Twin Frozer II 580 runs $540. The difference is $90, and that $90 went to pay for the bulk of the new power supply. And after tweaking the settings to match Bit-Tech's benchmarks the cards do outperform the 580 GTX by a pretty reasonable margin (43 fps 580 vs 49 fps) - I originally ran the benchmarks with everything enabled which is where I originally stated that the 580 and the two 560's traded blows, not realizing the 560's were set higher than the 580. And if you're not in the market for overclocking the reference EVGA 560Ti goes for $200 CDN. That's $400 for two, a whole $125 cheaper than the reference 580s' (here in Canada). And it's only about $60 more than a single 570 ($320-340 depending on MSI/EVGA/etc). Can't argue about that value though, a pair of 560's is a great "budget" alternative to a 580 or a 570.
