Well I've just sold my Leo's, so you missed a chance there Weight wise they offered little saving I felt. Having had them on my Capo I knew they were heavy silencers before ordering.
As I said to you at Dent, the Tenere seems to be a very loud single, I dont know why, it just is. Maybe with more time and inclination I'd look at making headers and staggering the join to try and change the soundwaves/pulses.
I've got something in the pipeline (no pun intended) at the moment for a single silencer, will see if it comes off.
When I had the Tenere on the dyno with uncorked Leos it registered 47.74 rwhp, but was running lean. The consensus was that with the stoichiometric levels addressed I could have been around 50rwhp. This ties in with previous dyno results here.
Torque wasn't measured sadly, but I have my baseline for experimenting with.