Disclaimer: I haven't been active on MGF since summer of 2013 so read all of this with that in mind (aka my memory may be a little off on details and I welcome someone else to weigh in):
Yes, briefly (I suspect I still have an account over there, I haven't logged into it in years). It's a shitty website. Don't bother. Lots of girls dislike MGF and there was a spree of girls closing their accounts right around the time I started camming. They have incredibly strict rules and as I recall kind of terrible payout. Also the majority of the women on MGF can be found on other camsites, so there's no real reason to pursue someone over there.
Some foggy details: There were bizarre contests where a premium member would post a challenge, receive submissions, and then pick a winner. In effect the contest-holder was getting potentially 100+ videos / pictures from multiple women for a small reward that went to benefit one model. There was also an issue with writing "blogs" for MGF that had super strict rules—you couldn't mention camming at all, even in passing, even though they offer cam services. You could write a blog post for the site and other models would flag it within minutes if anything could be construed as amiss, leading to rumors that there was a "clique" of women who basically controlled the blog and would flag everyone's content but their own.
Edited to add that they're super strict about offsite contact to the point of banning girls who don't even mention it—if a member asks for offsite contact and the model says no, she's still in danger of being banned. This sounds ridiculous, I know, but I remember it happening multiple times to other girls in the few months I worked over there. /edit
That said, it's possible I never clicked well with the site and other people love it. I was getting my start on MFC at the time and I did pretty well pretty fast so I was focusing my efforts over there. :shrug: Just my two cents.