I unclip on the left and only unclip on that side when stopping at signs and lights. But, I just realized, when I first start, I clip in with my right foot and push off with my left. I have speedplays, which are very easy to unclip, but when I fist used clipless and I had spds, which seemed to have an "easier" left side. I don't know, maybe I should change, because I am definitely stronger on my left side, even though I am right handed, my laterality is very mixed. I can barely take my right hand off the bike to signal, while extending my left is very natural. I have a lot of issues taking off from stops that are at a slight incline, even when I am in an easy gear. This has turned into an irrational fear of going down in traffic, so i will often take an alternate route. Maybe if I was pushing off with my left foot, it would be easier. It just seems unnatural to unclip on the right now.