Is the BMW M3 a good investment?

The thesis

The E46 M3 CSL represents peak naturally aspirated inline-six BMW engineering with a tuned 360hp S54 engine. Limited to 1,383 units Europe-only, none sold in North America. Recent UK sales show £62.5k–£95k for good examples, median £82,410. The SMG gearbox (not manual) reduces appeal versus three-pedal competitors but scarcity and low weight (110kg lighter than standard M3) make this a blue-chip modern classic. Appreciation has been strong but not yet parabolic.