When you promote a website/forum you have either paid or free. The general practice is if you don't have the money go free. If you do then paid. Paid is better than free. Free is still good because you can still get decent promotion happening. Paid is better than free because once you got everything right it's 100% automated.
I guess it depends upon the group you're aimed at. For many, it might be more beneficial to save the money and use it elsewhere to benefit the site while advertising at free locations.
