FC for the GT I cannot comment as I didn't have the the GT for an extended period of time.
For the standard K5, I would say FC is about average for a modern D segment.
Ride is good for it's class, but not exceptional.
Handling is something which I cannot put too much input on as I didn't really get to test it on twisty roads. On the highways and around town, I have no complaints.
This car was positioned as a Grand Tourer, hence it does that very well. High speed long distance drives.
The power delivery is very linear. It seems to accelerate from 120km/h to 160km/h at the same rate as it did from 40km/h to 60km/h. Feels like a big NA engine and is all very smooth. The interior is well done up and quite comfortable. Features like the air con seats and a panoramic roof gives it that premium feel.
If you want to win traffic light races, it is the wrong car. it just isn't tuned to accelerate in that fashion where other cars deliver most of their torque. It is tuned as a GT car, not a sports car.
If you are a safe family man who wants the smoothest ride for his family and has never driven past 110km/h (which is the speed limit on the highways), wrong car to buy.
If you are buying a car based on how much you can sell it in a few years, wrong car. Although Kia does have a Value5 plan to secure the value recently.
If you are driving from Perlis to Johor and need to pick a car in this segment, this is where it blows the competition out of the water.
It is not a boy racer type of car. It is a cruiser, and should be viewed as such.
You are talking about the Optima K5 aren't you? With the Optima GT turbo you can have both comfort and power. But the GT doesn't seem to be selling well. Maybe Naza has overpriced it for this market.