This is my OPINION...all are fine guns and the top of the heap.
I have never shot an Elite, but I have heard from a variety of people that own them that they probably have a slight edge in out-of-the-box
accuracy. However, whether you are shooting .7 or .9 inch groups really doesn't matter if your primary objective is hunting. I too am not a huge fan of the Disc concept; it is the sole reason I have never even considered a Knight.
I know a decent number of people with the Encore. While it can be a very accurate gun, this is the one that I have seen the most people struggle with. To start with, the barrel taper means you need to get a special set of rings to get the scope correctly mounted and zeroed without using up all the scope's internal adjustment. Additionally, there seems to be a problem with the hinge pin on the mechanism. Mr. Epp at Precision Rifle has a page on this problem, and a good friend of mine thinks he is currently having the same problem. Groups will mysteriously move around the paper for no apparent reason. It is a fine rifle and can be extremely accurate, but when I was recently in the market all of the problems I've heard of soured me to it. Additionally, individual guns of all models vary and I too have seen the high-charge accuracy problems. This friend's Encore will shoot 85 grains and 220 DC bullets .5-.75 MOA, but 90 grains are 2" groups and forget 100. He has tried a large selection of bullets with similar results. Other people's Encores may be different.
I actually just bought a thumbhole Omega recently. It had a stock defect, so it has been back to the factory twice and I finally ended up with a new stock...but because of this I've only put 8 rounds through it. However, the only two I shot without adjusting the scope went through the EXACT same hole. I can't say about shooting high charges through an Omega because I haven't yet, but I have heard some like it hot. Partly it's the luck-of-the-barrel. I don't quite like the way the action mounts in the stock; when I got it the barrel was partly free-floating but bound on one side. But if I was careful tightening the action screws, I could get it centered and fully free-floated. So I'll always have to be careful to get it in perfectly when I pull it out or it could change things.
Never give up on a gun right away. I had a Traditions that shot like crap for the first 200 rounds, then it became a sub-1" gun. It had a limit of 100 grains with most every bullet, but the 250 grain SST would go sub-1" at 135 grains 777.