????The supercar has been a struggle to sell, which means potential bargains for interested buyers.

????By Alex Taylor III

????Among the more exotic niches of the car business is the marketing of supercars.

????The cars, which carry price tags in the mid-six figures, require a tricky marketing balance. If they become too scarce, speculators move in, driving up prices and making the cars unavailable to enthusiasts. But if too many examples show up on the market, they lose the appeal of scarcity and potential buyers move on to the next big thing.

????Consider the case of Mercedes’s SLR McLaren. Based on its spec sheet, the car should have been a home run when it appeared in 2004. It had a supercharged V-8 engine that put out 617 horsepower and got the car from zero to 60 mph in 3.6 seconds; its top speed was 207 miles per hour. It sported an advanced carbon fiber body and retro scissor-style doors. The SLR also had a history behind it. It was said to have been inspired by the Mercedes 300 SLR of 1955.

????But the market for supercars was weakening when the SLR came out, and the car received some middling reviews. There were complaints about its styling and its function — whether it was really a sports car or a grand tourer in disguise. Mercedes had planned to sell 500 SLRs a year at $495,000 each, but after 2005, it wasn’t able to achieve that goal. It ended production of the car in 2009 — two years ahead of schedule.

????Today, the SLR is unloved and unwanted. According to one dealer, there are currently 26 unsold cars at the port in Los Angeles. Based on last year’s selling rate, that would be a three-month supply. A Mercedes spokesperson says that number is too high — she says “only a handful of SLRs are there” (though there may be more in East Coast ports).

????If you want to buy an SLR for Christmas, now is the time for a bargain. Mercedes says that if you group all the wholesale and retail dealer allowances together, you could knock the price down by $175,000. A dealer says the number is actually higher: $250,000 off the sticker.

????But if you think the SLR has become damaged goods, never fear: a new Mercedes supercar is on the way. The 2011 SLS AMG, introduced at the Frankfurt Motor Show in September, gets a 571 horsepower V-8 that will fling the car to 62 mph in 3.8 seconds, with a top speed of 197 miles per hour. In addition, it has genuine butterfly doors. The estimated price is $225,000 or less than half the price of the SLR.

????Caveat emptor.