Oh yeah, I sent you a note about this one - I've cooked with them before,
they are sort of gelatinous in texture, so a long slow cooking yields rich tasting tender meat, like ox tails. They are delicious, and are hard to find. There is one market here in Mill Valley (Marin, CA) that can get them once in a while.
I have a great recipe that uses beef cheeks, along with two not so other well liked meats - tongue and tripe. It's called Sonofabitch Stew by Trader Vic's and it's really good, as long as I don't think about the other "specialty" meats". Not having grown up eating them, any type of organ meat is just not my cup of tea (except for pate and foie gras!).
If you would like to see the Sonofabitch Stew recipe please let me know! It is my dear beau's favorite stew...