In one campaign, we started out using tokens of some kind on a battle grid. However, as the campaign went on, we stopped using it. For most part, it went okay. However, keeping track of where everyone can sometimes be too much. In particular, my character, whose modus is either hiding or healing, sometimes both, lead us to a situation when even I forgot to inform of our DM that I was hiding behind a huge statue that fell over. I was too busy keeping the rest of the party alive that I forgot where I was. Thankfully, when it was brought up, our DM just asked me to do an acrobatics check to confirm that I managed to roll out of the way and another check to see whether or not I kept myself hidden.

Keeping track of everyone's positions also became less important because our DM got a bit more lax about imposing those area of effect rules.