You should know a little bit about both in my opinion. I grew up wrestling and that was all i knew when i fought. As an adult i did kickboxing for several years just to learn how to fight standing up, but it is more of a chess match and the toughest guy doesn't always win a kickboxing match. I got into Gracie Jiu Jitsu just to get the combatives belt, and to try to just be really good at what i learned there.... but i try not to fight at all. In addition to that, just remember that getting tired is just in your mind and you can control it, and also never let your enemy see that you are hurt or tired. I learned that from my fighting coach, 2 time kickboxing champion Ronnie Diamond DeLeon. He is also a thai fighter with a dangerous shin bone, lol....