Buy it...You can sell it easily for $400...
I have an original Disc that I've had over 10 years, it's more accurate than I am...The only difference between the original is the extreme uses a red primer disc which gives a better seal...
With a Green Mountain barrel, adjustable trigger and bolt action type one piece stock that Knight will be a great hunting rifle...
Cleaning is relatively easy, clean the barrel, remove the breech plug, clean it and the threads inside the barrel, disassemble the bolt and clean it...It might take an additional 5 minutes to clean than some of the break actions because you should clean the bolt...I prefer doing that because of the adjustable trigger and one piece stock...You'll never hear a Knight owner that knows his stuff complain about accuracy...