but the rrd was cheaper, seems very little difference, I have also not heard nothing bad about them
Nothing bad - that's true but this board is much more technical than any other from 2012. She requires a precise driving. She is much demanding especially in high winds. You will feel more tired after 2 hours riding on it than on any other board from this season. However it's a good board for light winds but I would not highly recommend it.
I heard from one of a test riders that new K-rapida is a different beast - smooth, fast, easy to ride and forgiving. She should be available very soon, so I would recommend to wait for the latest realese from RRD.
Talking about the main topic: there is no answer which board is the best. It's easier to point out this season which one is the worst
I'm afraid you are not going to see any answers in such tittled topic. It's like asking which car is the best.
And winning does not mean all.
Put top riders on 2 years old boards and they are going to be still in the top in any competition.