None of the people commenting are Karate practicioners and have no clue what they are talking about. More 17 year olds weighing 160 pounds with yellow belts in BJJ commenting of something they don't know about.
People that are REALLY in the know in MMA/K-1 know full contact karate is arguably the best standup fighting style. It's certainly most complete. Taking FC Karate you will learn ALL the kicks they teach in Muay-Thai (though they are executed slightly differently, with more emphasis on hip shifting) and many more. It's the most comprehensive standup style, the closest to the Greek Pancratium; every bodily weapon is employed. In Japan karate is taken very seriously. They invited Muay Thai fighters to Japan to compete against the top FC Karate fighters, and the Karate fighters got the better of them. It's also proven in sport fighting/kickboxing events like K-1.
K-1 essentially determines the best standup fighter in the world. Succesful fighters in K-1 are either FC KARATE or Muay-Thai practicioners. No boxer has excelled in K-1. The "White Buffalo" Francois Botha (held his own with Tyson before being Ko'd) didn't make it very far. Japanese Karate fighter Musashi beat former renowned boxer Ray Mercer.
The current champion of K-1, Semmy Schilt, is a Seidokaikan(an offshoot of Kyokushin) Karate Fighter.
Kyokushinkai Andy Hug (called the "blue-eyed samarai" in Japan) won the K-1 grand Prix championships in 96 before dying of Leukemia at roughly 210 pounds, very small for a K-1 fighter. He also beat Mirko Cro Cop, a kickboxer everyone nuts over.
UFC heavyweight champion, King of Pancrase, Bas Rutten on his fighting background:
How many different styles of fighting have you trained in? Do you have any ranks? Who do you consider your teacher?
"...Kyokushin Karate 2nd Degree, Thai boxing yellow slip (just kidding), Kyokushin All round fighting 5th Degree (I received this after I defeated Takahashi. I didn’t do any test for this).
Anyone that has taken FCKarate and seen Bas take out opponent after opponent with close-range body strikes in Pancrase knows that's something they practice in FCkarate all the time. They don't allow you to punch each other in the face with bare knuckles (though kicking and kneeing is legal) because you wouldn't be able to train anymore if your jaw is fractured or your cheeks are broken. It is important training without gloves, because it is very close to real fighting, effecting how you block. You block differently with gloves. Enroll yourself with your cocky attitude and see how tough you really are.
The standup on UFC with few exceptions is pathetic. FCKARATE will teach you real standup fighting. Stick with Kyokushin, Goju-Ryu (or any okinawan style taught traditionally), stay away from Tae Kwon Do (point fighting), Shotokan (stances too deep, very linear). Karate is proven effective.
K-1 fight held under FC KARATE Rules:
Karate Fighter Andy Hug beating Muay Thai Fighter and K-1 finalist Changphuak Kiatsongrit
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Renowned Kickboxer Pat Smith (UFC veteran) losing to unknown Japanese Karate Fighter
Karate beating Muay Thai (Japan):
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Karate Kicking Demonstration (Japan):
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