A good sports cat is expensive £250-£500. You will need a remap but will benefit from about 20bhp, more torque and better throttle response. It will make the car slightly louder but a decat is needed if you really want to hear more rumble and get some flames out the back
No worries.
Got my sports cat from TSL motor sport in uk. Supposed to be made by the crowd who supply pro drive for the wrc cars so its anti lag proof. Cost £400