Making fun of the other branches is all part of serving and perfectly acceptable. It is those juvenile idiots who actually mean what they say that gives all of us a bad name. At the end of the day we need to be enlisting into the branch that best suits us, and not the one we think will make us look cool and or give us instant respect.
Serving in any branch is good for you. Some prefer the Army, while some prefer the Marines. There is good and bad in all branches. Once again, at the end of the day we need to understand that it is human nature to think we are the best no matter what we do. If you enlist into the Army, then why wouldn't you think you are better then everyone else? If you choose to be a Marine then why wouldn't you have a chip on your shoulder? It would worry me if I was in combat next to someone who didn't think they were the best.
You are not wrong with picking either branch and neither branch is the best. Just research each branch and pick the one that best fits your needs and try not to worry too much about what others think about either branch. At the end of the day those who go Marines will always have something negative to say about it, while those who go Army will always have negative things to say about it. I have learned that most who pick the USMC know full well they want to be Marines at all costs. So until you reach this point, it may be best to not pick the Marine Corps.
If you want to spend your enlistment or life slamming other branches because of bitterness, then go right ahead. Never let your insecurities cause you to question your accomplishments. Be proud no matter where you serve and no matter what your job is. Don't expect the Army to be like the Marine Corps, and vice versa. Different standards, different attitudes, and different missions result in two very different branches. We're not all cut out to live the Marine life, and some of us aren't up to serving in the Army. That is fine, just understand that different branches attract different people and we all are AMERICANS, so Semper Fi.