I've read a few of his books but did not enjoy them as much as many have reported. Like stated above, I found TR to be somewhat verbose and I would find I was forcing my way through until I couldn't take it anymore, then that title would sit for awhile until I gathered up the courage to continue on. The titles that I read were interesting snapshots of life in that time period but as enjoyable reads I prefer other authors.
On a side note, we visited TRNP a few summers ago and it was nice to put Hunting Trips of a Ranchman in a proper perspective. It is hard to imagine setting off with a wagon in that country in search of enough meat to provide for the ranch hands. I had also never heard of hydrophobia until I realized what we call it today - damn skunks!
Literary skills and questionable shooting aside, his establishment of the National Parks and National Wildlife Refuges greatly helped to bring conservation consciousness to be an acceptable attitude for the sporting public.