Without a doubt, the single most valuable purchase I've made in a lot of years. Recently was able to borescope a barrel on a new, unfired rifle, made an offer on what I saw, first-hand ( a hand-lapped barrel of the highest quality, and I've looked at hundreds), paid a reasonable price, and did not get the proverbial "pig-in-a-poke". The rifle is one of my best, but how would I have known what to expect w/o the "Hawkeye"? Invaluable in determining what cleaning procedures and solvents work, ( and more importantly ) which do not. I laugh when some make outrageous claims, when knowing nothing about what the bore really looks like, up close and personal. Ever wonder why you seldom see a used one offered for sale?