Strongly prefer a mix (so voted No). I go in 2-3 days a week and I use remote days for long tasks requiring focus and days in the office for shorter tasks or tasks requiring collaboration (and since I'm an industrial automation developer, I also need those days to run tests on the actual machine hardware).

The mixture also provides a significant social benefit. When I'm physically at work, I consider myself interruptable so will be more pleasant with people and more focused on useful collaboration - since I don't have any expectations of accomplishing anything large anyway. Conversely, I don't do meetings and will be much less responsive on remote days - those are the days I'm productive in code generation.