Interesting to see all the advocates and convertees to clipless I went the other way this past summer, putting toe clips back on my bikes. I found that the ease of walking in running shoes, which is what I wear when I cycle now, is much more convenient than walking in bicycle shoes with cleats, even shoes with recessed cleats. I also find it easier to get out of toe clips. As for pedaling efficiency, I'm sure that it is negligible. That said, it's always fun to get some new gear and use it for a while. Try them for a while and see how you like them. You can always go back to your old system.