Is it worth even spending money on full synthetic oils when the driver does a lot of stop and go driving in the city? I don't live far from work and since moving to the area there is a lot of stop and go driving due to 4 way stops and traffic lights. Also on the commute to work I really can't drive above 40 mph because of the speed limits (most of the time it's 30 mph). I'll do an occasional highway drive that can be from a half hour to two and a half hours once a month. I'm just wondering if I really am wasting money on these OCIs especially when I usually change them out at 5,000 miles.