A great looking car that is fun to drive. Its styling is distinctive inside and out. Some detractors say it's a "squashed bug" or "Porsche wanna-be", but the fact remains that it instantly generates love/hate comments from all lookers. Other manufacturers are copying the style, the Lexus convertible being a recent example. The interior styling is excellent too, particularly if the optional ball glove seats are chosen.
Long distance driving in this car is a pleasure. either on freeways or rural "twisty-turnys". I'm always looking forward to my next trip and it's hard to keep the smile off your face. You can find better cornering cars (boxster) or faster cars (the 225 TT or the S2000), but for the non-racer the 180 TTR gives great performance for the $. (Now that the S2000 has a real glass rear window it's also an excellent value, but for me the cockpit is cramped and the engine is unremarkable unless you keep the tach at the noisy high end.) The only negative I have is that the suspension can make the ride on some older poorly maintained roads a bit punishing.
Another important item for me is trunk space and the 180 TTR has the largest usable trunk space in its class (more than the 225 TTR too), large enough to hold my luggage, beach chair and boogie board for a vacation at the beach.
The bumper to bumper warranty and free routine service for 50K miles means the only thing you have to buy is tires and gas. With 23 mpg city and 29 mpg highway (excellent numbers for a sports car), you can't get much lower in operational expenses.