Wow, a lot of people got screwed over by networks. You should probably decide if the promises a network makes on services they can provide are worth what they expect from you BEFORE you sign. I wouldn't sign myself as I said in my original comment, I think it would be more rewarding to grow on your own. I have heard a lot of people praise networks however. If you have had a problem with a network its probably a bad judgement call on your part. There are 32000+ channels on Fullscreen alone and I don't think these networks could pull those numbers if they weren't in some way benefitting channels.
If you are thinking about joining a network for any reason weigh up the pros and cons for yourself.
Another possibility for the few people who commented about networks being negative could be you may have just chosen the wrong network for you.
Please stop quoting my comments now, I get it, you disagree.