They've been using these aircraft regularly on some of the transcons for the past year and it has been relatively easy to use them with the PMUs at only a small premium for K over LUT.
I have flown UA ps FC a couple of RTs and the service over there is so erratic as to be undependable. The seats are also frequently need of repair and the IFE machines that they give you are touch and go. And IMO the food ranges from OK to completely inedible. Like BlissWorld, I will now be staying with the DL product.
Probably the only things that UA has going for it with the ps first service are the lovely first class lounges but you're usually only talking about a 15-20 minute lounge stop on domestic flights.