The new Optima (called the K5 here in Korea) is an appealing car in my opinion. Kia Optimas, Hyundai Sonatas, and the equivalent of the Nissan Altima are all used as taxis in Korea. Every time I ride in a new Optima, I am really impressed with the ride and comfort of the interior (remember, I am speaking as a passenger).
You have already made your decision, but here is my take on Korean cars (for those who are interested):
Korea is a small country (half the size of California) of interstate-like highways that connect cities with not much in-between except byways. The speed on highways and byways are controlled not by patrol cars, but by camera systems placed on specific sections of the road (limit is usually 100km/hr for byways and 120km/hr for highways). In cities, it is either boulevard type streets or very narrow streets (by US standards) that cars have to crawl through. There are very few seldom used mountain/canyon roads (like there are in many parts of the USA).
Because of this approach to road design and urban planning, cars (re: sedans) made in Korea really shine at cruising speeds. In my opinion, there is not a domestic motivator for Korean car companies to build true sports cars. However, they are starting to dip their toes in the water and make their coupes more sporty (sedans too I suppose, but just adding a turbo does not equate to "sporty" in my opinion).
Finally, unleaded gas is approximately $1.80 (US) per liter, or let's say about $7.00-$7.50 per gallon. Diesel fuel is usually about $0.20 cents less per liter. LPG is around $1.00 per liter. When I go to the States on vacation, it is interesting to see the difference in Korean cars' engines from those in Korea. In Korea (like Europe maybe?), there are many cars (including small cars and SUVs) that have diesel or LPG engines (for obvious reasons). In the States, all I see are Korean cars with gasoline engines that could use just a bit more torque in my opinion.
Personally, I think the more popular Korean car manufacturers' products become in the USA, the more they will be able to devote resources to making their cars more "sporty." And by "sporty" I mean a car where everything (suspension, engine, body, etc.) is integrally designed with "sporting intentions" in mind.
!Thumbs Up