Hehe. Buy car must do research a bit. Read through V7 to V9 supposed to be able to help you. I am driving a 6 speeder. The gear change is smooth. U can't really feel or know that the gear has changed unless unless you look at your rpm. 110km/h runs at rpm about 2.3k. 130km/h is 2.5k.

I cannot comment on the 4 speed though.

6 speed already in market since 2011, you will find one easily but look at the depreciation is low, i would suggest you go for new one as warranty is 5 years.   

New Forte car interest offer is now at 1.68%-1.88%. Compared to second hand, the interest rate is around 3.5%.
If you take a loan of let's say 60,000 for 9 years, the difference in the interest alone is around 8,800!

Do build this into your calculation when you consider taking a second hand unit. Don't just look at the difference in price of a new car and a used car, look also at the installment you need to make every month. The actual cost is all hidden there.

Secondly, used car prices are OFF the road, you need to factor in the insurance (and sometimes road tax), plus the cost of name transfer and registration.

Good luck and hope you get a good deal whichever car you decide!