Beef Jerky done too quick?

I bought a Masterbuilt 40" propane 3 months back. I did the modifications recommended that I found on these forums. I made a few batches of jerky in it that turned out pretty good to my taste and my buddies love it as well. But When looking around the forums pretty much everyone says they smoke jerky for 5 to 6 hours or more. If I do that I will pulverize my jerky! ATM the lowest I can get my smoker is 190 to 200. I use eye of round cut 1/4" sometimes slightly thicker. Cure #1 and marinaded for 24 hours. My jerky is usually done between 2 to 3 hours no more. I usually vaccum seal it and tell my friends to place it on the fridge. Is this Jerky safe or should I be concerned that I might get a friend sick? I read all the safety on Jerky but they only talk about low temps not High for short time.