I know this is a fairly old thread (hey, it wasn't bumped by me!)

Endurance road bike with SPD cleats (4 degree movement) on MTB shoes. Tolerable for walking around, fairly stiff for riding. Pedals can be easily adjusted to make stepping out easier. I just started riding with the SPD/MTB shoe combo coming from a "loose" clip/strap setup and had no problem transitioning.

Also, they make combo pedals, SPD on one side, platform on the other. Plus the MTB shoe lets you pedal without being clipped in if you break something. Not the best, but its doable by using the actual shoe cleats themselves, not the SPD cleat.

But since being connected to the pedal is more efficient, be it "click-in" or strapped, you want one or the other for most of your riding.