I had one of these in my last house.
I was attracted to it as I lived in Woking. Now Woking has a reputation for being ideal for Rhododendrons and Clematis as it had Jackmans nursery, famous for Rhododendrons in Victorian times. They used to transport them by road by cart to London.
I was so fond of it I want to plant one in my new garden. Surfing the net I was very surprised to hear that it is considered difficult to grow. It was rather lanky but had two show of flowers each year. My garden was always rather neglected. The only care this poor plant got was a part share of rose feed designed for the rose which also shared the arch, and a very occasional water. Which goes to show that it must be about the soil and the fact the roots were protected ( by weeds!) .