Highest I've been had to be about 75 feet. Reason I say about is I had 150 feet of "camp cord" as I lowered my gun down the thingy fell out of my pouch. I completely lowered my gun and the other end of the cord was dangling half way up the tree. 1/2 of 150 feet is 75. My usual is 20-30 feet.
I kinda did like merc123 and would cut a cord anywhere from 20' to around about 40' I knew when to quit climbing when I ran out of cord....
these days I stay more grounded and when I do climb I stick around the 20' range...I ain't superman anymore and after having the bottom of my stand fall a few times it's real tough bear hugging a tree for 40+ft...
Api Grandslam Extreme + Hunter Saftey System= 45'-55'
I like to get up there because I can get away with more. I am kind of clumsy.