Andrew , running the P3 plugs and the standard JX Ninja pipe , as for price i would say they will be more than the Boss line .. The pipes are about $50 dearer than the FLS grp pipes which are one tough pipe ..

Prices just had a look at Online hobbies and the JX is $450 plus pipe , becomes a dear engine but the internal parts are some what cheaper than the GRP's , worked it out a while ago there was only $5 between them if you bought the same parts (engine,pipe,manifold,plugs,rod,clips)

Wasn't an easy decision which way to go as they are both great engines but i think the JX has a slight advantage ,only my 0.02c

Mick