First impression is that the 16 and the 12 have similar characteristics: very quick, pivotal turning; most impressive windrange; smoothness, and accurateness of steering; high and long jumping. Both kites are (obviously) used in different conditions. I found the 16 works with a little bit more bar pressure than the 12. The 16 makes it very easy to learn different transitions as it is very predictable but still quick enough to redirect when it matters. The low end of the 16 is (with the right board) on par with 20m kites. By moving the kite quickly apparent windspeed can be generated very effectively. That gets you going before those 20m monsters are even pumped up. The quick turning is a huge advantage in chop and bigger waves. I used the 16 several times in big waves. It rocks! I have never done that before with a kite of that size. I marked the relaunchability down because some of the 5th line systems or a Reckon kite relaunches better in certain conditions. JN offers a 5th line set (and as I understand it their new bar has it as standard) but I felt no need to go through the hassle of having another line. Relaunch is better than on any other 4 line kite I have used. The stability of the PDs is outstanding and as far as I remember I dropped the kite only twice so far.
Overall conclusion: perfect light wind kite to learn new stuff and go out in little wind with a kite which is FUN.
PS: Before I get slaughtered: I run a Kiteshop and we stock other major brands as well. The JN kites are more expensive for us than other brands hence I am not biased towards JN. I can ride what ever I want but I prefer the JN Primadonna.