I wear shorts for my commute as I have several pairs and change them throughout the week.........I have 1 pair of decent bib shorts I wear on longer runs.....as the shorts wear out I will change over to bibs I reckon as I cannot afford several more pairs of shorts.........bib shorts do cover the lower back....I find I am always pulling shorts up due to the size of my gut....and getting a cold back even on a commute.