I recently scored a legacy MCX new in the box for way cheap, and I really like it. Admittedly I only have like 600 rounds through it, but it is a mix of bullet hosing and shooting at range. It has a fast cycling action, but it is super soft shooting. With my scope up at 6x, I was able to watch my vapor trail and hits on steel at 600 on a nice day. Pretty rad for a lightweight carbine.
If you are looking at $2k, I assume you are talking Virtus, which is a good/ehh kind of thing. I personally like the gen 1 guns as they are a bit lighter, but come with keymod instead of MLOK, and the trigger is like 47lbs. The gen 2 guns (Virtus) have a heavier barrel profile, a heavier MLOK hand guard, cerokote colors, and a better trigger. They also changed up the gas system a little, which somewhat limits your ability to cut the factory barrel, if that's something you care about. Gen 1 barrels are getting real hard to find, if you get a gen 1 gun and want to do a barrel swap you will likely need a gen 2 bolt (rounded lugs instead of squared) to go with the new barrels, but the caliber change kits come with bolts, I think.
The handguard is a lot bigger (taller) then an AR15, I am kind of indifferent as I have big hands, but the way the keymod/mlok comes from the factory, it runs down the center of it, so mounting lights can be a little more challenging then an AR depending on what your into. MI makes a pretty good aftermarket handguard that solves this. The collapsible folder is pretty rad, but I like the aluminum skeletonized folding stock just fine.
They are gassy, but that is really only an issue when running suppressed, so we will leave that alone.
SUPER modular. Pulling the barrel is simple and done with a torx wrench. Whicked easy to swap from 556 to 300blk. The handguard slides off by popping the front take down pin which was a selling point for me. I can have a handgaurd with just a front sight and a white light, and one set up for night vision that will let me tuck my suppressor. This way I can go from a light weight, handy package without my can and laser on the front to full larp mode real fast.
I am currently waiting for a stamp for mine, I am having the 556 barrel cut to 12.5" and I have a 9" 300blk barrel waiting at the shop.
I don't think anyone would be disappointed with them, now that sig has worked the kinks out of them for a few years.