Seconded! (thirded? fourth'd?)
The SU-16 is fun, plain and simple. Easy to use, easy to maintain, fun to shoot. That being said, the quality just isn't there in comparison to the CZ. My first impression upon picking up the Kel-Tec was "wow, this thing feels like a toy!", and it does. I bought it anyways due to a good deal and the tacticool factor, and for the most part haven't regretted it.
...
It did blow up a few months later, but I suppose that's the risk you take in purchasing a plastic rifle.
I will be keeping the SU-16 when it is returned to me, but if I were to make the choice again, I would probably go for the CZ. Just my .02c.