I built an RB6 for myself a few weeks ago and finally got around to testing it. I ran at a small indoor clay track and I was blown away at how well the car worked. Stock setup and not a single option part. I did bend the front hinge pin brace but it was a hard landing.
If the car works as well outdoors as it does indoors I'm pretty sure it will be what I run at the worlds. Still going to stay with the B44 for 4wd.