Looks good, Price is a bit high and that inter-cooler looks like its seen some Bakersfield sized bugs but otherwise it looks solid. Bluebook in great shape is 7 but most wrxs hold their value better than KBB would suggest. If you can get it for less than 9 i would say go for it.
That grill surround is definitly aftermarket and pretty easy physically to install but your gonna have a hell of a time trying to color match 10 year old yellow paint. and 10 year old clear-coat. The bumper looks stock and it actually looks kinda nice with the 3 holes matching the 3 vents on the bumper.
As far as being a good car to buy, They are a hell of a lot of fun to drive, the tuning community is very strong and the engine will run for 200k miles at least, as long as it is well maintained and not driven excessively hard they are great cars.
Slow is Smooth > Smooth is Fast