Just did my Larini install yesterday on my MY12 Evora S. Huge thanks to Fasttoys for his help (in reality it was him doing most of the work and me holding the light and trying not to trip over myself).
I wasn't sure if I would need the resonator delete as I had heard that late model MY12s no longer had the resonator. That is NOT the case (at least on mine, which is a May 2012 build date). Mine had the resonator.
Also, MartinM was precisely right about the rubber hanger mounts. You WILL need to order the older hanger mount style (specifically, Lotus part #B132S0088F, should be about $25 shipped from your dealer). Would have been a huge bummer to do all the work of taking the old muffler off and then realizing the rubber hanger mount was the wrong size.
In any case, start to finish was about 2 hours (with 2 people. I don't know how people are doing this solo without going absolutely insane). The pictures in the non-S Larini install thread are spot-on. The only difference is that the S model obviously has a different style diffuser. I would recommend taping the inner sides of the outermost fins of the diffuser with packing/painters tape to avoid nicks/scrapes. Also, the two hex bolts just below the license plate holding up the diffuser are tough to get at with 90 degree hex keys. I would recommend using hex screwdrivers that can be used at an angle.
As far as the exhaust note with the Larini installed, I would say it's a dramatic improvement over stock. Idling is a deeper rumble, but not obnoxious at all. Below 3,000rpm/cruising, I would say it's about as tame as stock, but hitting the gas/above 3K is where you hear a big difference. I would say 4K and above under load the engine screams (in a very very good way). Zero "drone" of any kind (a la rice rockets with fart cans). Some popping/burbling as revs fall back to idle when coming out of gear.
All in, very very happy with the Larini so far.