I've used the arcs and agree they have the least leash pull of any kite I know of, but the slack lines do present a hazzard, especially on the water, and there is reduced chance of a succesful relauch if you recover the bar.
I've not used the mastair but on the warrior 9.3 I have been seriously overpowered and find releasing the bar is a very good way to neutralise a potentially dangerous situation, there will still be quite a bit of tension on the lines which takes getting used to but you would have to be EXTREMELY overpowered (35+Knots on the 9.3) before you are at risk of being dragged. In such cases if you are being dragged out to sea wait a minute or so (after a minute or so of such dragging the kite will have taken enough water on to prevent it relaunching) then release the kite leash from your spreader, you can save yourself and worry about the kite later. If you are on land then being dragged by a grounded kite is safer than being dragged by an airborn kite because the kite will hit the groin or sea wall before you and will stop dragging, no system is 100% safe but I like the predictability and relauchability of the flysurfer system.
If you have to solo land when severely overpowered its best to do it in the shallows and wait for the kite to take on a bit of water to weigh it down before disconnecting the leash and retreiving the kite
i've used flysurfer kites for quite a time now and can tell you that in bad conditions, the kite will stay airborne for too long.
i've seen a guy being dragged by a 5m warrior which was obviously trimmed wrong - the kite wouldnt drop - winds where 6-7bft side-onshore and it was quite a hassle till we got it down (the kiter was dragged about 200m onshore, the kite flapping like mad).
if you get hard situations with a big flsysurfer, you're screwed ... i was hit once by gusts of i guess upper 6bft and let go of the bar. i lost about 500m till i regained control of the kite and another 500m till i got the lines wound up cause the trailing edge had enough water so the kite wouldnt start, but every time there was tension on the lines, the kite dragged me like mad.
the only way i solo-land a flysurfer is to tie the safety somwhere heavy, let go of the bar an run to the kite.
I suppose a flysurfer (like any kite) can be dangerous without a correctly set up leash, I personally test all my new equipment's safety features in light controlable conditions prior to using the equipment in 'real' winds. I think this is such an obvious thing to do that I can not understand why everyone does not do it???
That said, there is always a chance that equipment failure of some sort can put you in a bad position so the option of totally releasing the kite when you need to should be available. That is why it is important to try and keep a couple of hundred yards of safe ground downwind of you when riding or launching/landing. I also carry a knife (just in case)
It is very easy to test and setup the flysurfer leash to ensure the kite does not stay in the air too long, email firstname.lastname@example.org if you need instructions how to do this.
Yeah I've noticed that with my LEI kites that if the saftey leash is too short on the 2001 Naish system the kite doesn't open up much and you get dragged. The leash needs to be attached to a point on the line that is a half kitespan from the bar. Kite span = square root of (AR * flat area) by the way.
I found that making my self a 5m saftey leash solved the opening problem with my 11.5m ARX but created other problems.... the "pullthrough method" seen on the 2002 kites (X2 etc) seems better, no need for long leash.
My C Quads never give me ANY problems when landing..... I can land them on the beach in 25 knots and they won't move at all....
Also landing a C Quad in the water is real safe as well..... it ain't going nowhere, it sinks!!