Street almost all the time. Its smoother and faster. On one part of my commute I have to use the sidewalk on the left side of a 4 lane high traffic road. I could use the street and command my lane but I would have to maintain at least 30 mph and I certainly can't. I probably would not get run over but I would be holding up a very large string of traffic behind me and thats just too stressful for me so the sidewalk is there and so easy and available I use it to escape this area then back on the road. There is no law against using sidewalks around here and some people use them exclusively, just not for me.