slowboat is spot on, with a kite the stall speed can not be "claimed" - makes no sense at all.
If one should use a scientific claim that could be used, it should be the polar max lift coefficient for the whole setup (actual wing not profile so also induced lift loss included) which is a unitless value that can be compared fully.
Even better, the polars for the whole setup at given Reynolds numbers - THIS could be awesome.
But I dont think anyone really got these values...
They are the ones we "feel" ourself when we change to a different wing of the same area, and can feel a difference in stall speed and recovery.
With recovery I think of the way some low AR wings can easily be recovered as they still have some lift above the stall point AOA.
Whereas other higher AR wings with thin low drag profiles, will stall very suddenly and very difficult to recover.
It is the classic "performance/agility/ease" tradeoff