I am still running the stock springs on carpet with foams. What has also suprised me is that I can run the same shore tyres all round and get a good handling car, this is the first HPI which doesn't have inherrant oversteer.
I am soon to be getting some alloy hubs for the front, simply because I am breaking a steering block and C-hub about every 2 meetings. It's exactly the same thing that happens, I clip the inside of a fast sweeping corner and the bottom of the steering block breaks where the screw screws in, and this then forces the C-hub to break. I do like bling bling so I will be getting other bits too, but the front hubs are for durability, and they only cost at the most 3 times more than the stock parts, so if they are bent after 10 meetings I will have easily got my money worth.
The performance difference for a club racer like me will probably not be noticed with having a lot of alloy. Also, I like my car to have that individuality factor and I'm proud of how my car looks