I commute 20+ miles a day and I've been using Shimano PD-M540's with Bontrager Solstice shoes. So far the combo has been great (I keep shoes at work).

The reason I like the Solstice shoes is because they have a recessed cleat position (like MTB shoes) but are more soft soled making walking in them much more enjoyable. (The sole is more soft rubber than hard plastic).