Someone with expertise/ knowledge on the area, i want to upgrade the diverter valve as i have heard the standard B5 A4 one is known to leak boost and have problems under strain, i have a bit of spare pocket money at the moment and want to get one as it can only do better for it i've heard, but i dont know which to get, its $120 or so without shipping for the Hyperboost one, APR is up a bit more i think but then there's this one on Ebay which looks the same to me, anyone know if its worth it or nah??
VW Audi Seat Skoda 1 8T 20V Turbo Recirculating Dump Diverter Valve Aluminium | eBay

 

Buy a genuine 710n, they're like $40

 

The ebay one will do the job just fine, like Pb said get a 710n. DV upgrades are usually needed for chipped A4's. Stock DV will do fine on a non chipped car but then again a DV upgrade is always a nice thing to have.