The 'proper' colour for the flowers is a deep wine red with darker burgundy underneath, which fade slightly with age to a deep carmine. There was a lot of variability in the seed stock I used, which was probably the result of an accidental cross. In 2005 I grew six, and no two were the same. Colours, markings and combinations varied from pale pink, dark cerise, burgundy red, charcoal grey with a pink flush, or pale pink and black bi-coloured. It's probably cross-pollinated with a 'normal' black and white flowered bean. Broad beans do cross very readily so it would be no surprise if an open-pollinated variety like this had picked up a few stray genes from a neighbouring crop. It'll probably do it some good, too.
They were all gorgeous, but I saved seed from the deepest red ones separately and it became true-breeding again in just a couple of years.
In 2006 I grew 12 plants, mainly from my own seeds, but topped up the numbers with two from the original seed packet. I now don't know which ones were originals and which were mine, but I can guess: there were 10 normal deep red-flowered plants and two pink and black oddities.
There is another old-ish broad bean with red flowers, Red Epicure ... but it's quite different, larger and with chestnut-brown seeds.