I switched from Pirelli's to Goodyear F1 GSD3's when I had my wrx and noticed an instant improvement, the car tracked better and took corners better. I recommend those. Got a horrid set of 19's on my current STi with TOYO Proxies on and I don't have no confidence going into corners like I had with the Goodyears. I know 19's are to big anyway but I bought the car with them on so will change em in due course.
I'll go back to GY F1's as they gave excellent grip and didn't tramline to any great degree. There is a place in Biggleswade that do a very good price on F1's to