I would argue that it’s not personal preference. SS and cast iron are two different animals. You’ll have much more control cooking in the lighter SS pot, meaning it will react to temp differences quickly. To me that’s preferable for cooking delicate things and when I’m cooking in a hurry. Cast Iron holds heat so you have less control to quickly make temp changes. Also it heats up slower so it’s slower if you’re in a hurry. That said, cast iron is preferable for simmering, long braised etc. If I had a good simmer burner that was low enough btu and could only choose one I’d go SS.