I got my AR10 A4 with the sole intent that it's going to be built into something that surpases both a stock Knights SR25 and an Armalite AR10 T. If you want to go real unique, save your money and go as box stock as possible.
As stock I'd rate the SR25 and the AR10 T as pretty much the same beast as far as performance goes. Over the years I've read reports from owners of both rifles where they've had problems with performance, head over to the biggerhammer link and you might find a few as well as find out how the problems were solved/fixed. Both Armalite and Knights rifles have had an occasional problem of not getting their gas keys staked to the bolt properly, if this happens the rifle will have shotty reliability and it hints that both companies have an occasional issue with quality assurance on the assembly line. Knights SR25s are also a bit finiky on ammo selection, most of the guys over on Biggerhammer will be able to confirm that and mention how they switched out the SR25 stock buffer so as to gain more reliability with other ammo types.
Also, I've heard that Knights Manufacturing can be a real pain in the ass to deal with if you need to return a rifle to have it worked on. If you try to buy new then you have to wait forever and a day for them to build your rifle, probably the reason most people resort to tracking down a used or LNIB SR25 when they get in the mood to buy one.
Armalite though tends to have better customer service and warranty speed, lifetime warranty with fewer hassles is pretty hard to beat.
The AR10 is a pretty cool rifle and I'm happy with my current AR10 A4 as it sits for now, I've developed a pretty decent handload for it that hovers right around the 1MOA area for 5 shots at 100 yards which is fairly decent yet it's still rugged enough to not have to treat it like some sort of gem. For a really accurate AR10 I'm gonna have a custom upper built, I'll switch out to it or amongst a few others and take pleasure in the diversity. I have a bit of a desire to own an SR25 but to me it would not be much more than just a "gee wiz" rifle that would just be a collector's piece to me and I couldn't drive myself to put any real hard useage through it.
The SR25 has it's "neato" factor going for it in that it's been adopted as a military issue rifle and that it's an exclusive hand made item. It's also very likely to hold it's value or even increase in value given time.
The AR10 is also "neato" in that physically it is closer to the AR15 in appearance and is a part of the Armalite history. I also like the fact that I can convert AR10 magazines from M14 magazines allowing me to have magazines for 2 rifles, even though you are butchering M14 tubes to get them into an AR10 it is possible to have a mag that will work in both an AR10 and an M1A, plus they are cheaper after converted than the SR25 20 round mags.
Somebody will likely add more but to me the Armalite is the way to go if you are going for a shooter.
