Pros
Lots of routes available to drive using your own vehicle, both in early morning and in the evenings. Get paid the same day that you drive. Routes are usually pretty tight so you're not doing a lot of long distances between stops.
Cons
Low pay for the amount of miles you'll have to drive. You may average about 20-25 an hour, depending on how long of a block you sign up for. But you'll end up spending at least 1.5 hours pay to put back into your gas tank. You can't choose the area you want to drive in, it's chosen randomly for you. So you could be clear across five counties from the starting point.