Sheenee, your kids sounds much the same age as mine - dd1 is Y4 - and we recently had a visit from RPA to talk to our primary school parents. I met the Head, a Parent Governor (I had already met, in fact) and a teacher, and talked at length with all three as did many of my friends.
I also talked to some of our primary's kids who started at RPA last September, and to a parent/friend whose dd is in Y5 at our school - and whose eldest started at RPA last term, after being moved from another Richmond school he wasn't happy at.
My overall impression is that things are definitely on the up. My experience with schools turning things around is that, once confidence starts to build in a few parents, there is a snowball effect and things get better fast - it happened at our primary, and it took about 5 years for the reputation to catch up with reality 
That said, I did wonder a bit about 'poster child' sales pitches - not from all three of the RPA people I met, but definitely from one. I know the AET people say 'the middle ones' matter hugely (ie not just the brightest or the most in need of help) but I don't know if reality has caught up with sales pitch here.
I do know that there are many, many interested parents in the area who are planning, or at least hoping, to send their kids to RPA. I am probably one of them (though still will investigate other options).