Very good posting. ^
The farthest I've ever thrown a disc via "usable golf distance" is 380 feet on a hole where you go down about a 10-degree grade for the first 325 feet, then up about a 25-30 degree grade for the last 75. Put the tee shot about 20 feet "below" the basket for a deuce-2. Felt like $1 million after doing it too...as it was just four years ago I couldn't ever hit 300 off the tee.
I've probably ripped a couple 425 or so (with a little help from grade, heat/humidity, and wind)...but they were junk throws...since I missed a good 80-100 feet left of the basket. "Flipping" a Boss or Katana a bit as a LHBH, then having them sail/glide in the wind for a mile. Pretty to watch, but worse than throwing it 360-375 feet accurately, since throwing it 360-375 accurately would give me a chance to make two...while throwing it 400+ wildly makes me have to save par with the up and down.
I've been playing (off and on) since I was six! Missed about 20 years in there with school, work and kids, but I've been playing since before we had baskets in our area. I still am generally only 315-320 feet off the tee after all those years. Would I love to hit 415-420? Absolutely. But if given the choice between throwing it 420 or being able to much-more-consistently hit the 30-35 foot putts? I'll throw it 250 off the tee...if "selling my soul" for something meant putting from 35 and having it look like the basket is about 4-5 times bigger than it actually is. ;-)