They dont last as long as Aluminium, Stainless or Ti cans, yes Vtwins are harder on carbon cans due to the stronger power pulses,
Susuki TLs will quickly destroy carbon cans if the packing gets degraded, the longer overall system length on Ducatis with underseat cans and I would guess the SD is the same, are a little more forgiving.......
I would suggest if you want to go with Carbon cans to keep an eye on the packing and to repack the cans regularly

I've had carbon sleeves on a number of Ducatis as well as the SD and never had any problems with the lifespan or integrity of the carbon. Like everyone says you will have to repack them every so often and this is the time to replace the sleeve if necessary. There are loads of places that supply all the different diameters of carbon sleeve so you don't have to go and pay Akro prices if you ever do need to replace.

Aluminium sleeved cans have the best bass!
But aluminium seems to have fallen out of favour with exhaust manufacturers over the last 10 years........ shame