In last years, it had reduced significantly, like once every ~03-04 months.
Most travelling had been in twin cities, from home to office, and back, almost 40-70 Kms daily.
If I can recall correctly, in Passo and Vitz, I did not mix any high Octane with regular fuel.
Passo had mostly been on regular fuel. In Vitz, I experimented 02-03 times with pure HOBC (again, not mixing high Octane with regular fuel), and found cost to benefit ratio to be more. Then I stopped using it.
I used to mostly refuel from Caltex / Total Petrol Pump in F-6 Markaz market, Islamabad. It had been regular fuel, and I never faced any issues, what-so-ever.
Pump seems to be great! 10/10
Yes. You may be right.
In my case, I always used to go for pro-active maintenance, along with routine maintenance, may be that's the reason, I did not face issues.
Passo was sold around 48-49,000 Kms. Vitz was sold around 45,000 Kms.
Both had zero faults at time of selling and handing over.