My opinion on it is that i would have no issue at all in paying a small monthly fee to be a paid up oople member.
On a car forum that i'm a trader on, i pay to be a trader, and the members can either not pay to be a 'full member' but this limits their posts to 20 a month, and they get delayed access to view items for sale. The paid up members can post as much as they want and can view items for sale as soon as they are listed. they can also PM anyone where as non paid members cant use the PM system.
its a tricky one, as making people pay to have more benefits does drive some people away, but if its a small charge and their are some benefits for paying up (ie early access to the items for sale), then i'm sure everyone will be fine with it
