Great job on those!
I think you can use just about any rub you like on beef ribs. The secret is to use just enough to add some interest and not enough to overpower the wonderful "beefiness" they have. They'll always shrink up quite a bit and they seldom turn out as pretty and even as pork ribs but my wife and I love 'em and make 'em often.
I've had good luck with several batches on the PBC, rubbed with just a little Montreal Steak. It is realy hard to get good, big, meaty ones here in the Southeast. Not as much of a "staple" here as in the Southwest or West.
Hub