Short commute, 6 miles each way so I use both clipless and platforms.

Platforms with clips and straps when I will be doing any shopping so I can wear normal shoes. SPD's when I want to go fast or otherwise want to ride at lunchtime. When it's really icy or snowing then just platforms because it's that much easier to put your foot down and I can wear warmer (bulkier) winter boots. I only have double-sided SPDs because I don't see the advantage to a single-sided SPD except for weight. No real disadvantage to commuting with clipless except for the need for cycle-specific shoes (and/or sandals).

Tried the eggbeaters but never got used to their lack of a positive 'click' but they were very light.