new disc extremes
 

looking at possibly purchasing a new one. anyone that owns the
newer ones that can provide any info pros or cons would be greatly appreciated. also the pros and cons of thumbhole verses straight
have never tried a thumbhole would love to see and shoulder one but cant find anyone with them in my area
thank you in advance

The new Knights are very nice...as good or better than anything they've ever made. The only drawback is the price that has increased. Right now they have some pretty good sales going on, and you can look at places like sportsmans warehouse or sportsmans guide and find fairly priced rifles often.
The best ignition imo, is the bare primer setup. Properly spaced you will have a tack driving, zero blowback rifle. I am partial to thumbhole stocks personally, have several Knights wearing them. They are very nice, and just "fit" me. Obviously its best to handle one if possible, you may not like it as much as someone else. Worst case if you bought it and absolutely hated it, you could sell it and buy a regular stock, or even trade if for a regular stock.
My preference (for my hunting style) is the UL. But its a good bit more than an Extreme. I like the shorter ligher configuration, but certainly nothing wrong with an Extreme.

The other option would be to find a used/like new rifle. They are out there all around, very fairly priced.

As far as the new Knights, I am a clueless puppy. Never fooled with any knights. Now the TH stocks on the other hand, I am quite familiar with! TH stocks, for me anyway, are much more ergonomic than your typical rifle stock. I personally just get a better mate with the rifle. Now all this is based on whether the TH stock is right for YOU and your size. TH stocks are most definitely NOT a one size fits all. The only real way to know if a certain TH stocked rifle would suit you is to feel it for yourself. Just like any other stock, a proper fit is needed.

I just picked up one of the .45 Knight Mountaineers with a 1-20 twist barrel. Quality of it is quite good. I made sure it has the thumbhole stock. The first thumbhole stock I ever used was an old Disc Extreme. Every muzzleloader I've bought since has either had or soon gotten a thumbhole stock.

I can tell you right now the TH stock is not for everyone and me included lol. I even handled one in Scheels but had the trigger guard on. What I found out after buying one is that my finger\hand isn't long enough to reach the trigger fully I have to slide my hand forward slightly while it isn't the best fitting I think it's doable and I just need to shoot more rounds. Once I start shooting and after the 3rd shot I don't even notice, but if I had to do again I wouldn't get the TH.