Alright, well I just picked up my special edition tan su-16 fx. Took it straight to the range an put 200 rounds through it, in quick succession. Not a single feeding/failure issue!
First off, I wish I bought this gun earlier! I love it, super light, looks awesome! Non-restricted ar style, 10 round mags, just a dream. I love the fact That it weighs next to nothing, and still folds very compact.
Comparing it to a vz58, very different rifles. The vz is very heavy duty, durability is felt the second you put your hand on it, and has a nice punch in 7.62. I love my vz, it was accurate out of the box and can use it as a sledge hammer knowing it will never break, fail or mis fire.
BUT this su-16 is just so light (you will feel the need to baby it, it's that light weight. You'll think its fragile), no recoil, compact, and still folds pretty well, it's hard not to love it. Me and a buddy tried to scenarios of throwing it back and forth (increasing intensity) to one another trying to shake something loose, it held up. Fired 50 very or so through it very fast, (put it in the bag, walked outside) intentionally dropped it in snow for about 30 seconds. Shook it dry as I brought it in side (in the case), and put a mag in, chambered and fired off 2 mags. No problem.
Now, the draw back to the fx edition, is the halographic (eotech style) sight. Terrible glare, so difficult to sight in. Not the guns fault. Get the lar15 mags. problem with the factory included tangodown polymer mag is, it's a little tight coming out.
Long story short, don't hesitate. Get one, my only regret is not buying 2.