Because of my bearish view of the economy/market I Havant actualy traded these for at a guess some years now. But to answer your questions.
"Are these thro' Barclays?". Yes but expect any other Brokers will let you trade them as well.
"Can you stop loss them". Have not tried stop losing them but works fine with limit orders.
"Do they muck about with the spread". Yes just like any other share in that respect.
"Also a bit cheese off with their changing spread at time watching" That will be down to our Market Making friends then -): again just like any other share.
"and difficulties of getting in to the B system". Tell me about it, Barclays have been absolutely useless over the last couple of months in terms of speed and customer services.
"Anyway, how are you?" Jogging along, glad the poxy winter's nearly over -):