Considering to have this toy and doubt about 12 and 14 I have found the follow strange aspect.
I don´t do it personally it is measurements another guy.
You put AERO 12 on the Aero 14. Just bend on the half area.
The kites are identical only Aero 14 has 30-40 cm longer wings. That everything.

It seems to me as a real minor diference.

please can you reply some experience who sail these kites.?
Bottom range top range ??

Petr