So some final feedback...
The thing that none of these charts show is the impact of the Tuneboy tune on the 40% throttle. The bike feels like a race bike below 6,000rpm and above 8,000rpm at full throttle but more gradual twist of the wrist gives strong linear power throughout the rev range. Add to this the sound of howling banshees and i'ts quite an emotive package.
I've decided to stick with the AR for now until I do the next service (or if I get a non-compliance sticker because it is bloody loud). Going to try the second baffle and I still want to get the heat shield fitted though, although it'll only be an issue in the heat of the summer. When I fit the Termis again I'll do the Tuneboy tune, and it would be great to see whether some of you East Coast boys get Wayne to tune your slips before then.