t99 :
I would be a little careful of the r9 280x for 199$, same card by the popular manufacturers is closer to 300$ and at least 250$. 280 compared to 270x is not much different it's like comparing the 270 to the 270x. the specs are very very close with basically more stream processors and higher clock speeds. It does look like though pretty much everyone does agree that the 270x is the best.
Is the best...how exactly? The 280x is better than the 270x, that's why it has an "8" instead of a "7" there. Granted, that's a low price for a 280x, but PowerColor is just a tad under other manufacturers, and I've seen their products get good reviews before.
As far as new goes, yes, the 270x is the best you're gonna do for $170.