For me, it all depends on the time of day and the amount of traffic. During the daytime, I'll wait. Traffic is heavy enough where I only wait maybe 30 sec for a light to change. It's not always, but most times. Now at night, I might see 2 or 3 cars in 7 of my 11 mile commute. I tried to wait. After 2 min at one light, I decided it was stupid to wait. I'm careful, but I still go.