I've recently purchased a C63 standard. So no PP or PPP. It has 19 inch rims and 4000 miles. Excellent condition and car all round with everything still very tight however... There appears to be a significant steering knocking sensation over bumpy roads. The column physically feels tight however there is a mechanical rattle that is transmitted to the wheel that is noticeable. I've done a lot of searching for this issue on forums and found some clear comments that this is a trait of the car. However due to the extent of the knocking when doing high speed driving on bumpy roads, the sensation can become disconcerting with a non-connected sensation coming through. How prevalent do the c63 owners find this? Anyone in Yorkshire will no doubt have similarly bumpy roads so Im wondering is this normal and the road conditions locally exacerbate the problem? Would welcome speaking to other owners who have experienced this as it's stopping enjoyment of the total package!