I worked with a climber, about 6'3" and 220lb so not that heavy but not an ounce of fat on him and he could one hand a 346xp, not a great idea but bloody impressive to see
I'm 6'6" and 240 pounds and love the extra reach I can get. Although I do get jealous sometimes when I have to limit my tie ins to a few spots that normal sized climbers would think was overkill. I've learned my lesson a couple times with smaller tie ins and am lucky to still be able to write this because they could have been deadly. I don't chance anything anymore and so far so good.