Here is a another viewpoint on the supposed 'superiority' of clipless pedals.
http://www.bikejames.com/cardio-training/top-3-clipless-pedal-myths/
Personally, I'm a recovered clipless rider... meaning I rode clipless for over 10 years before giving flat pedals a serious look. I suffered an ACL tear (due to crash where my foot didn't unclip fast enough), and I went to flats just during the rehab period following knee surgery. My plan was to switch back to clipless after a few months, but I found no real advantage to them after being forced to acclimate to flats. There is a learning curve when switching to flats, especially on rocky climbs, but at this point I have no plans to go back to clipless. Get a pair of 5-10 shoes and you will find that your feet stick amazingly well to flat pedals.