Until it blocks at which point it could be mega bucks but each to their own
I wanted some more power too so as I was getting it remapped anyway I thought it would be rude not too....
For info at MOT time mine blew 0.03ppm the limits is 1.5ppm the machine couldn't even detect that the engine was being revved with the exhaust probe so they had to connect a cable to the battery terminals to detect the increase in RPM.
HTH