To my shame we haven't really tried to propagate it, John we must try some cuttings this year. Well, I hadn't a memory of rooting it, but Ian tells me that he has made many plants from cuttings! Silly me! So, we must take some for you, John!!
It has a more restricted distribution than P. caespitosum, but we saw P. caespitosum used quite widley in the rock gardens of the Czech Republic that we visited recently. Some of those gardens are VERY hot indeed- well set up to a fierce sun, so I would imagine that both would cope well for you. Sandy Leven grows P. caespitosum well, as I remember (- though Dunblane is claimed to be akin to Atlantis!)
We have it ( P. hendersonii) on a couple of very sunny sites here - in the raised bed in the picture it is exposed to all the weather we get- cold hot, whatever. It seems very tough.