I had our first lesson of the season using the Waroo 12m in the week-end
and it was excellent.
The student was twice my weight (255 lbs .vs. 125 lbs) and we shared the
same 12m Waroo no problem.
The water relaunch was so easy and that's really boosted the student's
confident level. We also went through the relaunching technique using
both the flat kite technique and the the classic kite technique (the
student obviously prefer the flat kite technique as it was simpler).
The "submarine pull" was reduced by more than half.
The body drag upwind was easy.
The student originally wanted to buy a used 16m classic kite from the
school (for budget reason) and after the session, wanted to go for new
flat kite as he liked it so much (even though a new Waroo 16m is twice
as expensive as the school used 16m classic LEI).
Overall, I saw many advantages of teaching/learning using flat kite and
not any disadvantage except for the fact that the student may get
addicted to the flat kite and may not want to use classic kite.