I know what you mean. When I was using adwords, I use to just do the Google Search and not have them run on the network.
Although you can still make a ROI having your ads on the network, I just didn't want the hassle and work of checking the ads continuously. For example, with the ads on Google I felt like I could trust that and would therefore look at my Adwords account once every 15 days or longer. With having them on the network, that would have made me want to check every few times a day just incase I had a hike in the number of clicks due to new sites adding my ads or something.
Probably just a bit paranoid at the time, but would probably work with the network also next time.