It would be neat, but not likely to elevate brand image.
Plus, you really have to think about which brand image BMW wants to continue with in the future.
On the one hand, you have the purists -- those who long for the days when BMW built light, easily maintained sporting cars for reasonable amounts of money. On the other, you have the majority of the modern fleet: heavy, feature-laden cars with monster motors to keep the performance high.
They both have their place, but it seems the market won't allow you to cater to both groups. BMW has shown an interest in going for the "prestige" brand rather than the "performance" brand. An ultra-high-dollar supercar is unlikely to please either group, and Ferrari/Lamborghini enthusiasts will just balk and laugh and then not drive their cars more than 10 miles a year, hoping to keep the resale value stupidly high.
What I would love to see BMW try is something like this:
Continue with regular BMW models being excellent balances of performance and luxury. M models will continue to "dilute the brand" (so say the purists) and be insanely powerful, over-the-top vehicles with all the bells and whistles. Immense performance for every driver.
Add this mystical tii line to help appease the purists; keep prices in-check, and offer more "stripped" versions of the cars (sadly, still have to meet lame Federal regulations so this will never be perfect). Some smaller motors would be okay, but even a Porsche-style concentration on the I6 motor (both NA and TT) would reduce testing necessities for bringing vehicles to the US market. Lose the sunroofs, the power seats, the gimmicky this and that and just let people build the cars a la carte.
That said, the M1 Homage is über-hot to my eyes. At first, I hated it, then I kept looking at it. It either burned a spot on my cornea and my brain gave up trying to figure it or out, or else I had an ah-ha moment and realized I appreciate its modern reinterpretation of the original masterpiece (which itself is kind of ungainly and awkward until you spot it at various angles).
If introduced at an R8 price-point, an M1 Homage might sell, but probably not enough to make development worthwhile. If the economy improves enough, a Le Mans-derived supercar could be feasible, but unlikely to alter the brand image at-large. It might, however, attract less affluent customers to the tii vehicles and 1- and 3-series models.
Really, it's impossible to say. You can do all the marketing research and focus group stuff you want, but consumers are fickle, crazy nut-jobs. We make BMW's job very, very hard.
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