I have the 12x36 IS bino. I think it's a bit heavy and bulky. Stabilization works by rotating a prism, which causes color fringing when you make a large movement. I find that a bit annoying. Otherwise, it seems to work well. My wife loves it. If it wasn't her favorite bino, I would probably sell it.
For most people, a 10X bino doesn't have excessive image jitter. Unless you have shaky hands, image stabilization isn't doing much. The 10x42 IS model is about 10 oz heavier than a conventional bino. Merely adding 10 oz of weight to a conventional 10x42 bino would also reduce shaking somewhat.
I think the best IS model is the 15x50 IS bino. There the image stabilization really helps.