I like a nice rack.
The MEC rack bag I often use doubles as a backpack and carries all the daily essentials quite nicely and serves well as a 4th bag when I am touring... it will be become the 6th bag after I mount up the front racks and panniers.
In the winter I don't mind using a messenger bag or backpack as heat / sweating is not an issue but most of my daily drivers are racked out or will get racks built before spring.