Probably the quickest way to setup a GPS, is using a laptop connected to a little handheld unit. But then it's still a pain, if you're going to use it for stop by stop.
To line things up that are in a close tight area (like a regular route), it can make things easier, as the units will tell you what address you have the cursor pointed at. So you'll know if you can hit one address, then a culdesac, then the next when you come out.
For a spread out area, it's just a pain as you'll have to scroll and have an idea of where the street is. Search feature just takes to long.
If you want to drive with one on, it would give you an idea of how the streets run, paticuarly if you have some of those streets in which the engineers couldn't figure out if it should be a N/S or E/W street, and curve. This would help you figure out what they were thinking.