Toby wrote:North also has one bar size, no?
North was the pioneer of the concept if I'm not mistaken, but more and more companies have adopted it since:
-Naish (rather bogus implementation - still needs to be confirmed if it is actually effective at all)
-Zeeko / Starkites
-Switch (North's rip-off)
-Royal / Caution / Zian
I'm sure this is not even a half-complete list, just these I'm aware of from memory (and i've deliberately left of some small-timers).
The biggest con of adjustable bars is actually forgetting to re-adjust it when changing kites. Freaking annoying to go out on a light-wind kite only to realize that your bar is still adjusted for a 7m or the other way around.
Another "real-life" con is that you're buying into the whole "adjustable" idea in order to reduce the amount of bars you have to carry. However, you still need at least one backup bar anyways, especially on kite-trips - which kinda defeats the purpose.
The biggest "PRO" of non-adjustable bars is that most (adequate) manufacturers not only supply smaller kites with a shorter bar, but also with shorter lines. Imho a 6-7m kite flies a lot better on 18-20m than on "average" 22-24m lines.