Gardening Which has published their best buys for Runner Beans which may be of interest.
White Lady, heaviest crop.
Red Flame, heavy crops.
Runner/ French Bean cross. Developed by Tozer of the UK. Look like Runner Beans but do not need pollinating as Runners do, so you could grow in a green house for a very early crop.
Moonlight, white flowers, and Firestorm, red flowers. Not as heavy a crop as the top two runners.
Grew Moonlight last year. Did have loads of beans. But actually St George out cropped them.
I have saved some moonlight seeds so it will be interesting to see if them keep their attributes.
I am more interested in flavour than huge cropping.