Is the BMW M3 a good investment?

The thesis

The CSL (Coupe Sport Lightweight) is the ultimate E46 M3, shedding 110kg and adding carbon fibre, an airbox howl, and motorsport pedigree. Only 1,383 made globally, 422 for the UK. It's the last naturally aspirated straight-six M3 in the mould of the E30 legend and has already appreciated strongly from £30k lows a decade ago to £60–100k today. Still trades below stratospheric E30 CSL or GT3 RS money, and the S54 engine's 8,000rpm theatre is unmatched in modern M cars.