I fitted the exhaust without a PCV to begin with, but the bike was hunting for revs at low range, but sounded awesome and looked much better than the standard or just a slip-on. One thing you notice is the weight difference, the bike feels more agile instantly. The standard exhaust looks like it came straight of a Ford Cortina... Probably weighs the same too.
Jordan's in Leeds fitted the PCV & did a dyno run so it's got a custom map. The revs are smooth throughout the range and knocking out a measured 190bhp. Totally awesome.