First of all, I wouldn't consider any stabilised binoculars other than Canon's models. Canon got the compensation angle just right for astronomy at +/- 0.7 degs, perfect to eliminate handshake without causing a feeling of sea-sickness, a complaint of some stabilised binocular users. The compensation angle of Fujinon's Techno-Stabi binoculars is +/- 5 degs (i.e seven times more) and I found this most disturbing to use for astronomy while on terra firma when testing a pair of Techno-Stabi 14x40 against my Canon 12x36 pair. S & T also reviewed Canon, Fujinon and a Russian pair a few years ago and concluded that the Canon model was the best.
IS binoculars may not be to everybody’s taste but it is quite wrong to suggest they are a gimmick. It is not unusual to read comments like this from people who have only tested them for brief periods but ask people who have used them extensively and you'll get a different answer. I've been using Canon stabilised binoculars regularly for about five years; 12x36IS for a couple of years followed by a 15x50IS AW pair and 10x30IS on occasions. Personally, I find them excellent for binocular viewing, as I like to observe with complete freedom to move around as I wish without the hassle and constrictions of a tripod, sun-beds or gadgets. Also, as already said, great for weekends away and holidays to better climes.
I could see far more and deeper with the Canon 12x36IS pair than my Nikon 10x50s (hand-held), due in part to the excellent coatings but mainly due to rock steady views. The extra power and aperture of the 15x50IS pair is great for splitting double stars and viewing open clusters as well as nebulae etc. Like Damon, I don’t find them great for the planets but that doesn’t concern me, as my primary interest is deep sky.
Despite the aperture, the 10x30IS pair is rated highly for _casual_ astronomy, light and very easy on batteries. Leif Robinson (ex-S&T editor) reviewed a pair a few years ago and gave them a glowing report. The 12x36IS pair is obviously a bit heavier but nice to use and again reasonable on batteries. The weight of the 15x50 and 18x50 pairs can be tiring on the arms when using for extended periods – I do use a deck chair sometimes. Also, these models are more demanding on batteries but AA batteries are very cheap when bought in 12, 24 or 32 packages and the binoculars only take two at a time (use Ni-MH rechargeable if you wish). Always bring spare batteries as they can go without much warning. The larger pairs have tripod adapters and 5-minute stabilisation-on switches instead of having to keep the stabilisation button pressed as with the smaller models.
IS technology is expensive, although Canon reduced its prices substantially last year so better value now. To me, purchasing the Canon binoculars was worth the investment for the freedom it brings – I never use handheld non-IS binoculars anymore – just too shaky! However, others may find parallelogram mounts and other gadgets more suitable.
Gordon
  