Finally collected my 2013 C63 coupe on Saturday. The bar was set pretty high by the M3 I had previously.. but this has seriously raised the bar overall. The power delivery is far more useable without having to keep it above 5000rpm all the time like the M3. The gearbox isn't better or worse... it's different. It wins over the M3 for everyday driving.. a lot smoother, nowhere near as jerky, and always seems to know what gear it's supposed to be in. However when really giving it some stick, that's when the M3 takes the crown. Changes happen a lot faster and crisper (possibly due to having the M3 GTS gearbox software on my one) The interior finish is night and day between them. The M3 looked very dated and bland compared to the C63, with it's piano black trim, red leather and little aluminium trims everywhere. Even the colour screen in the speedo really adds to the quality. Toys and gadgets are another place the C63 absolutely smashes it - M3 had nothing you'd expect on a top of the range 3 series. The C63 has EVERYTHING! (whether or not it all comes as standard, or the first owner of mine just ticked every box, i'm not sure) The sound - We all know what the result here is going to be.. Overall, in my opinion the AMG smashes the M pretty much everywhere you'd want it to for a daily driver. When it comes to fast road/track though.. the M is a different league.