It all depends if you want to go faster or have more fun. My S3 has standard shocks, narrow track, and hasn't been set up apart from the post build check and I fitted an LSD (diff had to come out anyway, so why not? ). On the road, the car is easily fast enough without an LSD and with standard shocks. My off road events have all been untimed events where having fun has been the priority, so donuts and power oversteer has been great fun. I haven't encountered understeer at all, but that's probably the way I drive. If I was into sprinting or more serious circuit driving, then I know I would be best spending money on driving tuition, then set up, then shocks and last on an LSD. As with all upgrades, I suspect you know in your heart what you really want, and it doesn't actually have to make much sense. After all, any sensible person wouldn't buy a Seven Duncan