Recently, I made some new friends in college who have had a long-time martial arts background (Muay Thai, Wrestling and BJJ). I told them that I'm an amateur boxer who's not only a diehard boxing fan but also big MMA fan. They told me if I'm interested in enhancing my fighting background and make a career out of MMA, then I can come over to their gym.
I've thought about the two careers and analyzed the pros and cons of Boxing and MMA.
Pros: Much more paycheck, more globally mainstream, rich history, more press freedom (compared to UFC/MMA), slightly more respectable athletes.
Cons: More higher risk of permanent head/brain injury and in-the-ring death, being a world champion in boxing has now become meaningless with multiple alphabet world titles from multiple unnecessary sanctioning bodies, a world boxing champion can cherry-pick their contenders if they wanted to and get away with it more often.
Pros: Very fast growing sport, slightly less shady underhand tactics than boxing regarding fights and promoting a fighter, less likely to suffer from permanent brain damage and death than boxing, no world champions are allowed to cherry-pick their opponents once they sign a contract with a promotion/organization/league (UFC, Bellator, etc.).
Cons: Less paycheck, still only popular in a few countries (even in Brazil, MMA isn't all that well-known as a sport), outlandish and exaggerated promotion of the sport.
Most Helpful Girl
Do you have wrestling experience? Can you stop the takedown? Submission defense? That whole floor game just doesn't have any equivalent in boxing at all.
If you're thinking seriously about making this transition, watch the James Toney-Randy Couture fight from a few years back. Toney was a very accomplished boxer, and he got his ass handed to him in the first round. Watch that fight, and see all the skills Toney didn't have, that you'll need to develop.
Boxing is also much, much more rulesy in general. There are cheap shots in every fighting sport, but you'll have to be much more willing to give -- and take -- them in MMA.
Most Helpful Guy
More money for now in boxing, and you're further along in it, so i wouldn't be super inclined to switch.
Even if you do switch later, having high level boxing experience will be a 'selling point' in mma.