Perhaps he was reffering to the game mods.I was unaware of there being multiple half life games out right now....
I'd go with the 9800 Pro, I have two of these beasts, one standard card and one AIW, and they both perform very well in HL2 and a variety of other games, without any overclocking.
And the X700 is out of the question since it's a PCI Express card...