I don't think I ever have except for the overpriced ones I bought when I took college night classes... I have had my eye on this one for more than a year but figured it would go down in price... no such thing.
This is the definitive work on the Colt 'snake guns' of which I only own one now... that is my mint 1970 Colt Python. Not a lot has been written about the snake guns cause they are complex and expensive soooo little real interest in expensive books about em since no that many folks own one. Basically they are 1900's revolvers tuned to perfection with LOTS of man hours.
The Python is king. 140 pages are devoted to the gun.... I would put the Anaconda (44 mag gun) near as cool but not as well finished.
Sooooo... My Python..... I would say at this time it is worth maybe $4k to the right person? $3k is more realistic. Historical and cool? you bet. At that worth.. it somehow does not seem like such a large investment to buy the book from the most famous authority on he things. so I did it.