Just a note that specialized makes excellent clipless compatible Cadet shoes for ~$100 (the cleats are recessed but not much). I use the lighter weight Shimano PD-A530s with them adjusted to the lowest clip spring setting. Their platform is not going to tear up the soles of your shoes. If you bring the cleats with you, your LBS will fit the correct size shoe for you and install the cleats. Worth the few more $$ IMHO.

Amazon.com : Shimano PD-A530 SPD Dual Platform Bike Pedal : Sports & Outdoors

Specialized Bicycle Components

My only gripe, as others have mentioned, is that sometimes its difficult to get the platform side up when you want to do so quickly and end up riding more on the insole until you can get things straightened out. I don't think clipless gives me enough of an advantage over platforms to be worth that hassle... but I'm still working on my pedaling technique.