I have the Nashbar combo SPD/platform pedals on a couple of my bikes. I like the fact that I'm not married to having to wear bike shoes all the time. For example, if my son and I decide to ride down to a park, I don't have to worry about transporting shoes and changing; I can just hop on the bike with my tennis shoes and go.

There is a learning curve to getting the right side of the pedal up (regardless of which kind of shoe I'm wearing), but it really isn't that bad.