To be honest even though they advertise on Tom's front page I am not blown away with the Palit brand. If you read the newegg reviews for this card it seems they sent different versions to review sites than they are shipping to the consumer. The poorly worded "replies" ( excuses ) from the manufacturer sure do not say "quality brand" to me. I would get a good known quality brand like MSI, EVGA, Asus or Gigabyte myself. All will overclock quite well.
Generally, I agree with the "poorly worded" part of your comment. However, keep in mind most of these brands (Palit, MSi, Gigabyte, etc) are often times manufactured overseas. And therefore some of their staff that you interact with speaks English as a second language.
So far as different versions of the Palit GTX 460. There's an article about it, and it's been addressed in the forums, stating that the difference is the lack of VRM heatsink on the retail versions. So basically, the memory runs hotter (potentially less OC headroom).