Any sort of shank will work here. One important tip on dealing with large shanks: Use kitchen twine to tie them tightly while cooking -- this keeps them together and compact. Mostly it's for presentation, but if you skip this step you run the risk of the shanks falling apart in your sauce. Not always a bad thing. Make this dish when you have a little time, as it will always require at least 2 hours, and probably more. Good news is that it reheats beautifully, so you can make it on a weekend and eat it during the week.