First of all, Myvi is B-segment compact while i10 is A-segment compact. Malaysians majority are more family oriented and space is always priority therefore Myvi gets to sell more.
The i10 despite being smaller, it is made heavier to pass basic EU safety standard with additional weight added to the base of the chassis for making the car higher. i10 is over 100kg heavier than Myvi, that explains why i10 is more stable when cornering.
Since i10 is assembled by InuCom, expect some minor mistakes made by the assembly plant idiots especially those goyang kaki management. Make sure you inspect everything on delivery day if you bought i10. They do correct the tiny non-technical clumsy error for you FOC.
FC wise, if you kept revving hard like mad due to heavier chassis especially if you are used to driving lightweight A/B-segment, worst you get is 12km/L city driving for the 1.25L kappa engine. If you drive normal, you can get 14km/L and if you go lightfoot without stuck in traffic much, you can still get the 16km/L. From my result, I rated i10 slightly better than Vios FC.
Myvi is nothing more than cost cutting empty shell with 1.3L engine. Reason why Myvi could beat i10 in acceleration mainly because it doesn't have to pass EU/US safety standard therefore, they don't add any weight to bottom to make sure the car stable.
Handling stability, maintenance & reliability/durability wise, i10 wins. RV, acceleration and interior space Myvi. You go test drive both then you decide. If you're a lady and you need safe city car, go for i10. Please note i10 FC in city driving is better only if you drive patiently due to acceleration 0-100km/h difference between both cars at 2s.
A very comprehend review. I am very light footed as i am driving 10 years Kenari and i usually drive on 2k-2.5k rpm. Any other weaknesses besides its size?