Charlie, I have the same exhausts and was a bit concerned at the lack of heat shields (or mounting points for them) but it hasn't been a problem; apart from last couple of inches at each end of the silencers, the outer skin stays at a reasonably sensible temperature. On the other hand, going by the discolouration of the silencer at its ends it probably would take your skin off very easily.
One thing I would look out for is that the forward end of the silencer can is fastened with small Allen screws - a couple of them on one of my pipes were determined to work loose the first couple of times out, but have settled down since.
