The magic arm has worked perfectly with my D50, but then again my D50 is fairly light compared to higher end Dslrs. Vibrations are sometimes a real pain, especially if the road is a tiny bit bumpy, but most of the time I can pull off good rig shots at any shoot. I really want to buy a sigma 10-20mm (not sure if it's exactly 10-20), so I don't need to use as long as a boom. Right now it's about 10feet long while using the kit 18-55mm lens.
I like your tripod set up, seems real steady.