In short I've finished off the build, it was mega fun and the kids lover playing with it just as much as I enjoyed building it. I was happy with how it looked pre-decals, and didn't really want to ruin it with stickers, but in the end it looks really good with the decals now.
The only issue I have is that the rear cv joints keep falling out on extreme jumps and bumps, I've tried to replace the stock ones with a new dog bone (recommended upgrade) but even they keep falling out.
Here are some snaps before it was driven, it is now really scratched, but the idea is that we play with them right?!