VW Golf GTI Mk7 — Best Engine Oil for Sri Lanka Heat?

Just bought a 2016 Golf GTI Mk7 and want to make sure I'm using the right oil for our Sri Lankan climate. The manual says 5W-30 but given Colombo traffic and heat, should I go 5W-40?

What brands are you Golf owners running? Castrol Edge? Liqui Moly? Mobil 1?

Also, what's the oil change interval you follow here — 10,000km or shorter due to the heat and traffic conditions?