I was never disappointed with any of my impreza's. I have had a 2005 2.5 RS with sport package (basically a wrx interior, moonroof and wrx wing) and a 2005 WRX (which I currently own) and a 2009 STI (which I currently own).
The only thing I was disappointed with is the crappy paint on the 2005 RS. The paint holds up much better on the wrx and STI.