The one great thing about having an active board on RC is the traffic you get. It makes you much more visible to potential new members. However, with such a large and established club like FMAS, I doubt if it would make much of a dent.
Another issue about having a website is the maintenance. People move, drop out of the hobby, etc. Just make sure that more than one person has all of the pertinent passwords and passes them along!
With that being said, it is very nice to have a forum all your own. We set our own rules, but make no mistake, those rules are definitely enforced. We do not allow lfs bashing, either, but you can sell whatever you want (as long as its legal...we had to ban a member for selling undersized livestock he had collected). And the mods are the board members, so that can be good or bad, depending on the situation.
Although our forum rules very different, we do have reasons for each of them, and I suspect the RC mods have very good reasons for the rules they enforce as well.
It does take money to run your own forum, but it really isn't all that much. I can't remember the exact number, but it's pretty reasonable.
Just a few comments from someone who's been there.