tetol, you are right about a quality job with Mark
it is suprising how much BHP you can gain from a well made system. All our bikes on the garage have Marks handiwork on them somewhere - be it cans or system.
My bike gained 4 bhp from std, on the dyno just by putting on a good qual set of his cans. The viffer increased too.
The Lawson has a full system - as does the tri-colour & both put out more than stock.
Alan has already experimented with a std ss 2 into 1 system & feels it isnt worth the saving on getting that & adapting it.
C