I LOVE my Sub 2K. I consider it to be the best $320 I have spent on a gun. It eats everything I have fed it (Tula, WWB, Remington JHP, Hydra-Shoks) and is accurate as all get-out. I keep it and a couple of spare mags in a laptop case in my truck with me all the time. Here are a couple of tips:
1. Get the butt extender from Kel-Tec. It is cheap, makes the gun a lot more comfortable to shoulder, and doesn't increase folded length. I also like that it protects the front sight when folded.
2. Get the buffer tube cover from Tacti-Cool. Dirt cheap, and is much nicer than putting your face on a metal tube on a chilly morning.
3. The accessory rail fits perfectly. In fact, I just ordered a laser/light combo from Midway to try out on mine.
4. Get the G17 model, even if you can find the G19 model. Because of the way the weapon works, even the G17 model has a pretty short grip. I have fairly small hands, and I find the G17 model to be just right. I thiink the G19 model would be too short. However, if you still want G19 mags to fit, you can carefully shorten the grip with a dremel to take G19 mags, or you can have a pro like Dale at
http://www.gripreductions.com" onclick="window.open(this.href);return false; do it for you.
5. While you have the Dremel out, take off about half of the mag release. It sticks out ridiculously far. I am a lefty, and I dropped a mag twice at the range because my trigger finger hit it. 2 minutes with the Dremel, and no more problem.
6. Consider a Hogue Handall. I just put one on mine, and I love it. It makes the grip fill out nicely.
7. The trigger is pretty atrocious at first, but it will lighten up and smooth out quite a bit after a couple hundred rounds. Its never gonna be great, however.
Other than that, my biggest advice would be to enjoy it for what it is: a compact, pretty accurate, folding carbine that is effective out to about 100 yards. You will see some of the mall ninjas on KTOG putting scopes, bipods, bayonets and other junk on the Sub 2K which, IMHO, is completely ignorant and misses the point of the weapon entirely. If you don't get carried away with it, it is an extremely economical and effective firearm.