I am using combo pedals. I have Shimano easy-click pedals that have SPD clips on side and are platform on the other. Love em. I usually riode with cleated mountain bike shoes that allow me to walk with cleats on.
I was using Shamino clipless until my foot got stuck while pulling over to wait for my wife to catch up. I went down and broke my elbow, radial head fracture. Crappy injury, I still haven't regained full arm extension, probably never will. All the physical therapy people guessed how my injury happened........ A thin guy with a broken elbow= cyclist with clipless peddels, they see it all the time.
I use Shimano combo pedals too. I almost always ride with cleats. Shimano makes a SPD cleat that allows multi directional release cleats (SH-56). Even allow you to pull your foot straight up to release. I recommend them to people just renewing their riding with cleats or for people that have never used cleats. I used them for commuting for about six months before I went back to a standard release cleat. It's usually while you are "multi-tasking" (stopping, watching traffic, down shifting, pedestrians etc) that your foot release is last on the checklist and doesn't get done. Usually sales people have been riding with cleats for so long they don't remember what it's like to be new to them and downplay the training cleats and they were much younger when they did fall over, as I was.
I use them with some Five Ten bike shoes that have a sole that really grips the pegs on the Wellgo pedals: http://amzn.to/1MvUfje
I immediately noticed a big difference with these pedals compared to the stock pedals on the Ui5. It was like my feet were glued to the pedals, so I could easily and confidently apply much more torque to the pedals. I found I was often in a higher gear going up hills than before and of course this meant I was getting more exercise, and my motor was less likely to bog down from going too slow up a hill.
Also I can spin much faster with these pedals, so instead of spinning out at about 28 mph in the top gear, I can effectively add speed up to about 34 mph just by spinning faster. Before my feet would feel like they were going to fly off the pedals at the higher spin speeds.
Given how well these pedals and shoes work for me, I will pass on using clipless pedals and avoid the problem with forgetting or failing to unclip at a stop.