I think it's all a very subjective matter. What will you be using the car for? A DD, light track car, track car? It all depends.
For me the WRX fit my needs/wants perfectly so I didn't even look at the STi. Now I know others who are the complete opposite and the WRX wasn't an option for them. Like I said, it's all subjective.
That being said, I think the more important thing is to make sure you're in the financial position to be deciding to get something that is 10k more than it's counterpart.