Mums, what do you think: soy sauce or salt to season, if any is used at all?

A bit of soy sauce is fine. Do try to find those which are naturally brewed without added chemicals. Dark soy sauce has caramel added, so a bit of light soy sauce will do. http://www.kwh.com.sg

Soy sauce produces the same level of saltiness with a lesser amount of sodium. Hence soy sauce is healthier but do use in moderation! http://munfitnessblog.com/is-soy-sauce-healthier-than-salt/

I would go with good old salt. That being said, it largely depends on what you're making! :)

thanks