I'm 86kg and tried every kite I could get my hands on. I ended up with a 14 Contra and it really pulls like a truck. One of the boys who is 5 kg heavier bought a 17 as well but has almost never used it.
The span is wider (ie the kite is flatter) than the Switch even the Crossbow. This translates to more effective area. So a 14 Contra would have a low end slightly better than an old 16 C.
The best way is to try the kites one after the other and you will really notice the difference.
Heard from the shop owner that he liked the 14 better than the 12. I tried them both in different weather so I can not really give a valid compararison. Can tell you though that the 14 rocks.
