The only thing that bothers me about RFL and the like (and "bother" might be too strong a word, more of a niggle really) is the fact that due to it's "unique" atmosphere it will never be taken seriously as a running event thus reinforcing the whole problem around the very misguided notion that real races are "intimidating" and women are better off doing their own thing.
I think it's brilliant that RFL has introduced many women to running, but I don't think it's just the "women only" aspect that attracts them. The organisers have created a very emotional event where women come to raise money and celebrate someones fight against cancer or to run in memory of someone who lost the battle - this is why they come to run and I can't help wonder if they could maintain or even build on that special atmoshere even if they let us men join in - but perhaps not, I don't know.
But what I do know is that there are thousands of alternative races available and despite my belief that it's a misguided concept, it isn't something I should be too worried about.