The sport of mixed martial arts has become very popular over the last decade.  Mixed Martial Arts or MMA, incorporates some of the most brutal martial arts fighting styles known.  It is also said they are the best, real world application of self defense.  There is a problem with this type of thinking, however.
The martial arts were never been developed for sporting purposes.  They were always for real world self defense, which normally were used to destroy their assailants.  The various martial arts in MMA encompasses styles of fighting that have been used in the real world to kill, such as Muay Thai.
When it comes to real world self defense in America, using some form of MMA could create major liabilities for you in the civil arena.  If you happen to break bone, maim, or kill your attacker, you face lawsuits, court appearances, and even jail time.  Even though you have every right to use whatever means possible to protect your own life, our justice and court systems are so detached from logic, they do not think you do.  For some odd reason, your life and the life of the criminal are on the same playing field in court, even though that criminal valued your life quite a lot less if he wanted to take it.
Learn use of force methods to prevent an assault on your life where Muay Thai might become too destructive.  Be able to take down an assailant without breaking or injuring your opponent.  It will prove to be safer in the courts, not just the street.
After writing all of this, do not give up on Muay Thai or Jujutsu.  There will be situations in your life where they will be essential for survival.  Just do not believe that using an MMA style is the end all be all.  If you survive on the street using MMA, you may still lose in the court.