IMO, they are fantastic. The Extreme is a great gun, if you get it...I recommend getting the bare primer ignition setup. I heard Knight has a decent deal going on Extreme's right now, but I haven't looked into it. All my Knights shoot very good if I do my job. I am shooting BH209 in my Disc style rifles, still using pyrodex in my MK85's.
My favorite is the Ultra-Lite. Not sure what style hunting you do, but for me that is the ultimate rifle...if I was buying new.