Fabric pots or plastic on a west balcony that hits 38C in August Containers

Compromise that works for me on a similar balcony: fabric pots inside a cheap plastic outer pot. You get the air pruning and the root health, and the outer pot stops the wind and sun stripping moisture through the sides.

Group the pots together rather than spacing them out. They shade each other's sides and the microclimate in the middle of a cluster is noticeably cooler and more humid.

Plastic, in light colours, and go bigger than you think. On a west balcony at 38C the binding constraint is your once-a-day watering, and fabric pots dry through every surface, which is exactly wrong for your situation. The air pruning benefit is real but it matters most for plants staying in the pot for years, not for a tomato that lives five months. If you buy plastic, get 40 litres rather than 20 for tomatoes, put them on feet so air moves underneath, and mulch the surface. A large pot is its own thermal buffer.

Whichever you choose, add a self-watering reservoir or a simple wick from a bottle for the courgette specifically. Courgettes in containers at 38C are relentless drinkers and they will be the plant that defeats your once-a-day rule.