I am using Petron + 10W-30, have done two oil changes and it is a nice oil, car is Altis 1.6 2015.
In my previous 1.3 2NZ-FE, I used TMO during warranty period and) then started using Shell semi synthetic (grey pack which is now HX-7) with original Toyota filters and for some years I used Guard filters also. Then for a couple of years I used Petromin 20W-50 and found it to be very good. When our trusted Petromin distributor shut the business I switched to Caltex Havoline Formula 10-30 and continued with original Toyota filters till I sold the car after exactly 10 years with 134,000 km on ODO and engine was in great nick, just like a new engine both in terms of looks, quietness and power. Fuel economy remained great throughout and I never had to take car to workshop for anything other than routine/periodic maintenance.
The gist of the the story is that whatever oil you use, if it is original ( I mean not repacked used oil ) nothing bad is going to happen to the engine.
My friend's office has around dozen Corollas which they use for field work across Pakistan mostly in rural areas and his fleet had been running more than 200,000 kms in good nick with Shell ka lal dabba and guard filter.
