it is a piece of cake to OC it, using some software called rivatuner, or nvidias own drivers (after a minor tweak), or the ATI drivers.
BUT...
Reading the first of the links I sent you you'd find that there are grave concerns over the longevity of these cards if they are OC'd, as they may be from a batch of GTX's that were having a lot of early life failures, and overclocking back to GTX speeds may result in failure (I think it is a software OC and therefore you'd be safe to return it, but it is a hassle)
I am using one, and I could get running at 1600Mhz ram speeds, like the GTX, but it would artifact at 60C (thermal limit reported by nividia to 110C) I can only get artifact free performance at <1500Mhz, I have a good case with regards to cooling and airflow. So it does not perform like a GTX.
So question why you want one, if you want GT< performance < GTX performance and are happy at that price, then do it, if you are looking to reach GTX don't do it, unless you only want a card for 3 months or are expecting to send it back and will be happy with a replacement time of 3-4 weeks (in fact as it is a limited run I don't even know what they would replace it with...)
I'm happy with mine, 1280x1024 in BF2 with everything on high & AAx4 at very good FPS...