@ TotalHeadache - I would think ideally you don't want vsync, because it puts a a HUGE amount of more work on the GPU. I'm not sure if anything below a 770 could handle vsync on ultra settings.
@ the count - congrats on the new parts!

Lower Ram latency is always better, but you won't notice a difference below 9, same with 1600Mhz speed, no point in going faster.
For your graphics card, I'd suggest a 760 if it cost around the same as a 660TI in your country. A 760 performs better than a 660TI, and nearly as well as a 670 in a lot of cases, plus it (should) cost less than a 660TI.
I wouldn't recommend to SLI a 560, better off just getting another new card. 560 in SLI will consume more power, produce more heat, and perform worse than a single 760. Plus with the 560's you'll only have 1gb of vram (that's right, when in SLI the vram doesn't add up), which could be a bottlenecking situation. On a 760 you'll have 2gb. A 760 is currently Nvidia's best value.