Hmm...found the same issue with the wheels on my SC10. I'm going to use Nortech longer pins, put some araldite around the wheel pin slot to reinforce it and get some of those Fastrax wheel nuts!
Also read on another thread about using a washer on the outside of the wheel to ensure the nuts aren't getting to the end of the axle thread and will nip up tightly to ensure the pin is nicely engaged.
Be interested to know about the other updates as Cooper asked
Anyone got more details of these?