I have flown these extensively. As with all things there are pros and cons.
Firstly Hector, I would suggest adding the tension sticks on the back of the kite. This in addition to the new bridle words really well and should help prevent some of those flat outs. It puts a slight backward curve on the leading edges which helps the kite on rotation. They also put a slight curve on the vertical spars. This bows the kite that way also and allows the kite to spin around when flat on th e ground, leading edge to wards you. (effectively there is never a dead position)
These things are not for everyone. They are of limited use in team unless you are competing and intend to use advanced tricks. Individuals may find the variation allows them to do other things. There is always a compromise to be paid. For me I find that these bridles make rotations and turns fantastic, however, they make sliding a little harder (stands to reason as you no longer have a flat kite).
So it's horses for courses. I would encourage anyone to try this, but don't lose your old bridle as you may want to put it back again. Better still, buy another kite and have both! 
I use the (we call them Quad Sticks) on the back of most of my kites, but we don't put enough tension on them to actually curve the leading edge or the down spars, more so just to keep the sail as flat as possible, makes for nice axles flat spins floating is amazing flick flacks and ground recovery are also enhanced, the way these are set up is more of a torque converter meaning when one wing decides to fold over the other follows (probably why some call em training wheels, sissy sticks, or whatever). some people actually call them Magic Sticks.
In any case their main use is parking leading edge down and not having to stake LOL, all the rest of those really cool benefits are like a side effect.
Maybe its the way mine don't curve any spars but I have no problem with slides, they allow the sail to bellow just as much (as some would disagree) I'm not worried about additional weight I'm not flying indoors, but if made with some extra care they can be done with very minimal added weight like the ones on my SUL's
Some love em, some swear they are useless (whatever) personally I think they look cool and very mechanical looking and also add great function to the point when I get a new kite and fly it I can't wait to get home and tie up some quad sticks on it.
Now I've heard so many times "
real quad fliers don't use sticks" now bear in mind these are people that like to throw stats around, from what I gather more European and world champions use them so it's all personal preference, they don't impair flying, although they kind of help playing in water as they keep the sail from folding up like a book and if you have wind over 5 mph you can fly regardless.
Now these French bridles (turbo) I sat here and tried to tie up a set using that picture ( little difficult not seeing how its knotted) but after finishing it looks like the whole bridle is pretty far away from the sail and they measure out pretty perfect to the ones given in the photo, now on another forum somewhere they seemed to be very tight to the sail, any insight seeing as you have them from where they originated ??
