I had to abandon to using the Karai I'd bought (copper bottomed one) due it to rocking wildly whilst cooking. I suspect this was due to it not being a gas hob (electric instead) and the pan being simply too light to be stable. A heavier one might have helped I suppose.

What I have ended up using is the Kadai that Tefal recently produced. It has proven an acceptable alternative to cast iron casserole dishes so far. I don't tend to use a wok, unless I have made the sauce in a separate pan and am just using the wok to fry off dry ingredients and combine for the last few minutes.