I don't believe body size has much affect on the trip, certainly doesn't with LSD, but I'm 6'1", 190 lbs. 300 gave few visuals, but it was enough to tell they were just around the corner. Next time I'll try 600, and not eat the solid stuff that settles to the bottom of the water. Gotta say I was pleasantly surprized by the results, wish I'd tried this years ago.