I prefer Theatre of the Mind, but my online group prefers using minis (technically images on a computer screen, but you get the point). My players enjoy it because it gives them some visual reference, but I find for myself it's actually a little distracting. It's harder for me to acknowledge that there's more to a place than just a giant white vinyl Grid, or that there's supposed to be a ceiling in this cavern, while going TotM allows me to more vividly imagine what's going on, I find.