Lots of choices available and it depends on cost, as we have systems from £374.00 through to £1000, it also depends on whether you want Y pipe back or Cat back...
We fitted a Milltek system to a GT4 a few weeks ago...
Which Milltek system did you opt for, resonated or none resonated...
We've supplied and fitted a few and the resonated needs a little more volume and the none sounds superb...