I hear the RRS bubble is dual mode and is hand built by elves in greenland.
I should hope so the money they charge for it. Personally I use a tripod so I've not thought about IS in a bubble. Wonder if it really could combat fluid jitter.
I've just bought the "Seculine" electronic one, bit expensive but miles better than the "air bubble" ones
Are bubbles not 100% accurate all the time?

How is it better?
Can bubbles break? Do they need batteries? Can they malfunction? Are bubbles not 100% accurate all the time?
I don'tWhere do you buy RRS stuff in UK???
THREE Bubble?
Bit of an upgrade on the double bubble. That for the wideangle?