First thing to do with a B4 is a get a
TBE, FMIC and a retune to get rid of the VOD. The VOD is a void of torque when the turbos are switching over from primary to secondary. The
TBE is a must anyway. The FMIC helps to lessen the effects of the VOD by providing extra air volume for the engine during the turbo switch over. But the tune is the most crucial part and is necessary to almost get rid if the VOD.
Other than that. they are a good car and after the mods you can expect around 180kw ATW making the B4 and nice little sleeper. Its also the type of car that tends to fly under the radar when it comes to police and modifications.
I thoroughly recommend them for anyone looking for something similar to a WRX but with a little luxury and a little less attention.