I've been plagarized... I'm calling a lawyer.... Oh wait, I stole this idea from some other RCU poster. never mind.
I have essentially the same design with all 2x4's and it works great. I've had up to a Saito 1.25 on it and it's rock solid with a cinder block on the back of it. I could actually get it to slide a little with the 1.25 full throttle with an APC 17x4W which was a little cool.