I usually do the 2/3 choc to 1/3 cream
Me too. I have only made a white choc one though, for my white choc mud. I just follow the recipe, but I'm pretty sure that's the ratio.
YES! Use good quality chocolate Makes all the difference. (Like using wine in your cooking, I'm told - use wine that you'd want to drink ) And same with mousse - I think a good chocolate mousse has GOOD chocolate in it!