Shatner, I have to agree it is not very easy to use.
Over the years I've used stuff like adcyvcle,phpadsnew as well as hosted like renegade and adspeed. DFP is the worst in terms of initially getting to grips. I had to go on the phone to my google rep, could not get the campaigns to go live properly.
I guess two nice features are setting floor for adsense and adsense in a new window. Oh and free.
Currently using adspeed and really like it, super simple and easily set up nutiple geotargeted, capped ad with daisy chain defaults etc. Literally took me minutes.