I used clips and Sidi MTB shoes without cleats. I planned to go to a clipless pedal eventually, and once I get my bike back under me I totally still will. I'm a little apprehensive about it and a lot broke right now.
The stiff sole REALLY improved my ride. I had foot pain after 5 miles when riding in sneakers, and that was cured instantly. Hill climbing improved a little, too. Shoes = good! I never tightened my straps on the toe clips, so I expect the same would be true on platform pedals.