JustForFans (Just For Fans) is actually good site, but what I personally didn’t liked was their support (they seems so unfriendly to me personally).
Actually their revue share rate 70% is quite low as competitors are offering 10% more. Another thing I don’t like about them is quite bad designed platform.
And why you need to register with Twitter? This makes no sense for me as all competitors support email registration.
I suggest you to check these alternatives if you are looking to make serious money and 24/7 friendly support with well-designed platform with many features.