I have recently had the opportunity to test and evaluate (read "send a bunch of ammo downrange") a Kel-Tec Sub 2000 in 9mm Luger. Kel-Tec offers the Sub 2000 configured to use a variety¹ of readily available pistol magazines and they were kind enough to send me a test unit configured to use Glock 17 magazines.
When I picked it up at my local FFL, the gun was packed in a no-frills but form-fitted corrugated box and included a sight adjustment tool and a "key" to lock it in the folded position. Prominent on the lid of the box appears a large amount of American pride. In addition to the stylized American flag Kel-Tec logo, there are a series of smaller flag logos signifying American-Owned, -Made and -Parts - yeah, I like that.

At 16.1" folded, the weapon is small enough to easily fit into a backpack, briefcase or laptop bag. (Or the available soft case from Keltec).

Spartan to the point of homeliness, this little ugly duckling comes into its own when you do what it was designed for - just shoot it. The cheek weld on the buffer tube leaves something to be desired (I believe a God' A Grip Customizable Cheek Pad ² would be a very nice addition) but "as-is" it is amazingly accurate.

The sights were off out of the box - but the groupings were tighter than this old man's eyes have a right to do. The sight adjustments are pretty straightforward - loosen a Phillips head screw with the supplied tool and then tweak the fluorescent blade up. Side-to-side sight adjustments are done with the hex end of the same tool by backing the locking pad out on one side and tightening by the same amount from the opposite side. Don't over tighten!
During my testing I've put over 300 rounds through the Sub 2K - a mix of Federal, Remington UMC and Tula. From the first magazine to the last - no failures whatsoever. That includes alternate loading the three different products in a single mag - still flawless.
Kel-Tec brought this little beauty (grin - it grows on you) in at a very attractive price point - $409 starting MSRP. Davidson's shows models other than "basic black" as high as $446 MSRP. It looks like they retail for $300-350 - if you can find one in the wild. These puppies are scarce!
The nice price point does open up some neat options - some I feel are must haves - some tacticool. For the must have list - the stock extension and more magazines. It works beautifully with the larger capacity mags as well. If you'd like to mount some type of optics and still retain the "foldability", you'll need the aluminum forend (available with two or four picatinny rails) and a good quick release scope mount.
Aside from being a fun gun to shoot, I see some strong utility. Take it hiking/backpacking, four-wheeling, working the back forty - a handy little truck gun. Due to its compact size and accuracy, it could also easily fill a niche as a home defense gun. Hmmm...might need to cycle some defense rounds through it...any excuse to head back to the range!
I'd love to see it in God's own caliber - preferably using Springfield Armory XD .45 magazines. Being able to share mags would be wonderful. Even without that option, I'm loathe to return this little gem. I foresee another purchase in my near future.
___________________________________________________________________________
¹ The 9mm SUB-2000 is available in the following magazine types: GLK17, GLK19, S&W59, BERETTA92, SIG226.
The .40 SUB-2000 is available in the following magazine types: GLK22, GLK23, BERETTA96, S&W4006, SIG226.
² I bought one of God' A Grip's Cheek Pads and put it on my Ruger 10/22 - I'll likely buy more. Good products.
FTC Disclaimer: Kel-tec was kind enough to ship this weapon to me via my local FFL for testing and evaluation. I paid the requisite transfer fees and purchased my own ammo for this test. The God' A Grip cheek pad I mentioned, I purchased with my own money. I will very likely purchase a Sub 2000 in the near future. I received no wheelbarrows full of cash for writing this review.
(...and bite me).