I got a second hand 280 GTX with a Thermalright cooler on it and with the Fan on, the GPU temps and Memory RAM never seen the GPU go over 53'C. I don't have the fan on it tho, since the optional fan holder on the case window on the antec 1200 forces it off. It will also remove the ability to run SLI...but either way, its awesome. If you could get the Arctic Cooling one in S.A...I'd say that would also be your best bet.
Doesn't look like there is VRAM heatsinks included, so a DEF NO NO. The RAM runs hot if not properly covered in sinks. And most 3rd party coolers need a tad extra case cooling to get the full potential out of it.