Here is what i think, and i will comment on stuff i am sure.
A) Kia Forte is a C-Segment car, biggest car among the 3. CKD quality. The highest FC among the 3. Resale value is about the same as a Fiesta.
B) Ford Fiesta is a B-Segment car, same as a VIOS. CBU quality. FC consumption, i am not too sure. DSG gearbox, i think FC should be very good. Resale value pretty much meh.
C) Toyota Vios is a B-Segment car, average of the two. CKD quality. Proven very good FC. My bro is driving one. So i can vouch for it. Good resale value.

Now the question is do you need a car with boot space? Would a larger car be better for you? Or you looking for resale value? Reliability for 3 cars, they are all good. Hardly read any bad comment among them.
If you need a bigger car with boot space, then it is forte.
If you need resale value and proven car, then it is Vios.
If you want a car with plenty of safety and latest tech, then it is Fiesta.

Personally, i would take Fiesta given the 3, but that is just me.

This post has been edited by Madgeiser: Jan 8 2012, 12:07 AM

Car is categorized into segment, it goes from A to D. It is a way to categorized size of car.
A-Segment is where all the supermini comes in, cars like Mini cooper, MyVi, Suzuki Alto and etc which are small.
B-Segment is where all your entry level sedan are, these are typically cars like City, Vios, Mazda 2 and etc.
C-Segment is cars like Altis, Civic, Mazda 3, Forte and etc.
D-Segment is cars like Camry, Accord and etc.

CKD means Completely Knocked Down car. Meaning the cars is assembled locally and uses a certain percentage of parts sourced locally. This is to lower down the car taxes, so the manufacturer can sell them more competitively.
CBU means Completely Built Up car. Meaning the whole car is imported from oversea. It is not locally assembled.

DSG, generally means a dual clutch auto transmission gearbox. Normal gearbox is single clutch. I am not sure if it is Volkswagen first comes out with it, but i remember seeing Volkwagen cars has it first. Splendid thing.

Try google about it somemore. Plenty of resources online.

Addendum : I think the newest Fiesta comes in 7 airbag, last one is for the knee. Not sure if Fiesta sedan has it, but the hot hatch has it.

This post has been edited by Madgeiser: Jan 8 2012, 10:52 PM

My first car was a Hyundai Getz, got it in year 2005. Still driving it today. Resale value is pretty much phooey, but it is a good car. Pretty good looking one too!