Part way through my build now. So far not impressed with the build quality, it's definitely a downgrade from the M05. First issue I've run into is the P7 suspension balls pop out of the arms way too easily, they popped out several times while trying to screw in the king pins. Second issue is the o ring in the drive shafts cause the suspension to bind badly so I had to leave them out.
The arm plastic seems very different to the rest of the kit. They feel rubbery, trying to snap them off the parts sprue just lead to bending and stretching of the flashing. That's probably to make them flex instead of break in a crash.