I'm sure most people reading this know it already, but if you don't, the Geforce 4 Ti4200 is coming out by the end of this month, and its price will pretty quickly drop to the $150 (or certainly $180) level. It has substantially better performance than the Ge3Ti200 across the board, and will likely overclock to Ge4Ti4600 levels.
On the Golden Sample, I've read speculation that these aren't part-selected. Otoh, Gainward is the only manufacturer that acknowledges that the Geforce cards can overclock quite easily. I believe that they will honor their warranty within a certain overclocking range (about 10%). Not that any manufacturer is likely to prove that you overclocked a card to such-and-such level and ruined it. Cards do fail occasionally, even when run completely in spec.
In other words, it's not clear if Gainward is getting "special" GPU's from Nvidia. It seems to me that it wouldn't be worth Nvidia's time to do this sort of advanced bin-sorting. If Gainward is buying higher-speed memory, then that is obviously something to consider, but I also don't know that that is the case. Look for <5 nsec memory on a Ge3ti200, so that it can run its memory clock over the specified 200 MHz.