Since everyone has been really focusing on the interface and their personal preferences...
I am forced to work on CB, as MFC does not allow male models. I have never had any
serious issues with it except for the competition, which I sorta trained myself from day one to try my hardest to ignore and just do my own thing.
On CB, you are not only competing against other female models, but also male, trans and couples. This has sparked a massive trend towards hardcore being the default and raised a lot of the customers' expectations and their sense of entitlement. If the room next to you is hosting a free gangbang and you're just trying to get your top off... it can be rough. In addition to this, you are also competing against "Exhibitionist" models, who essentially give everything that you are trying to make a living off of... 100% for free... Something to keep in mind.
Despite all that, from what I have heard from my peers, the inter-model competition is
much more directly fierce on MFC. The MFC Premium Member system can allow members to lead you on for ages without ever tipping (CB actually just instated a new policy that requires members to spend their tokens within a set period after purchase - so no sitting on that one token), and they can PM/MFCMail you whenever (a double-edged sword). On CB, PM's are initiated either by those who pay for the privilege (not incredibly common), have mod status (who shouldn't be harassing you when you're working anyway), or by you, the model.
I obviously don't have experience on the model-side of MFC's interface, I can't really speak on that topic... but CB is pretty straight forward once you dial in your settings and figure out what bots/apps you want to use (if you even want any, I didn't use any for pretty much my whole first year). I think there are some recommendations on the
Chaturbate Thread if you're interested. Also, I'm 90% sure you can just hit Tab to switch between public chat and PM; not that the interface is ideal by any means but you can sift through them pretty quickly that way.
Support... oh boy... To be honest, I don't think I have
once heard back from MFC after putting in any kind of report. Harassment/stalking, underage (with documentation), abusive behavior, models breaking model policy, models obviously scamming members - nothing, not a peep. This is no smoking gun that they don't take action, I've simply never personally heard anything back at all. With CB, usually you go through a lot of the same crap you would with any Customer Service: automated responses (which will get thrown into a pile and addressed when they get around to it), severely delayed responses, dismissal, etc. I have, however, had many very quick and efficient solutions with CB. My guess is that they get overflowed with reports for literally anything you could possibly imagine because CB's traffic can get a little toxic, so it can be hard to sort the wheat from the chaff - but if you speak clearly and professionally, it tends to yield better results. Keeping them on your issue until it's completely resolved is not a bad way to go about things either.
Each venue has its advantages and disadvantages; since you have the option, why not try both?
Wherever you end up, good luck!