The majority of swedish aikikai that I have seen uses a rather high stance (probably due to a heavy Kobayashi and Nishio-influence) so I´m mostly curious about the mainstream aikikai-thing.
On the technical side: I find that the extended back leg of the old Iwama kamae (like Tomita sensei)leg really doesn´t give you more stability, and the more narrow stance (but not as narrow as H) gives you both stability and is easy to move from. So in a typical swedish fashion I go with the middleroad between extremes