i learned on LEI bows, i used my venom² on snow and never on water,i tried a P3 10 which is more or less the same wind range than my V² 13.
on light wind, i d pick the P3 over my V² , it has a better low end but as the wind climb, i d keep my V² cause it turns faster and i m used to its capacity to absorb gusty winds without havint to play with the bar all the time like bows (god i hate that)
but.. if it crash on the ground/water, FS > PL, depite PL autozenith will prevent the kite to crash a lot of the time (and it s priceless when learning tricks) but u r not protected from a lull or a no wind moment..
the SA2 19 has more or less the same weight as a P3 10 or 13 and is lighter than any LEI for light winds (2.8kg), that s why it ll stay in the air at 4knots.
now, i don t think in light winds, u ll manage to kiteloop it easely( not sure if u can even loop it..), FS r not very known for turning fast but r better for power/hangtime ( paraglider style), u can do all the newschool moves with the P3 10 and smaller sizes but i guess it d be easier with a PL arc or LEI C kite ( like looping a Ckite vs a bow kite, it s easier/faster with a C-kite)
now, for my point of view,since i m a beginner kiter and a snowkiter, i don t see the point for me to go to LEI, PL/FS or the future ozone vision have enough turning speed/power and easy relauch for me (reverse lauch like open foils, self lauch, no pump)and before i reach the point of being like Lenten or sponsored and doing all the extreme freestyle, i ll stick with the foils but if they manage to make LEI more solid on impacts.
if i had the money and in my region it s often 6-12knots, if i had the cash, i d pick a SA² 19, at the 10knots, u can jump already high with it and do old school moves, it s freeride/oldschool oriented anyway.
like i use to say, FS r bows without a pump.