RM130 is cheap.. it is cheaper then SHELL HELIX Ultra or many other make fully syn.
I am using Bardahl 5-40 Fully Syn and it cost only RM80 for 4 liters. So far it perform much better then Idemitsu and Castrol Semi Syn and SHELL Helix Ultra as
Only way I can measure the performance is to feel the engine roughness... Bardahl comes in after 7000km while others you may feel the roughness after 4000-5000km
May I know how you choose your oil? 10-60 is a good range for our country as 60 is good as 40 may be too thin.