Hi Steve;
I do use other bones but I use skulls part of the time (depends a lot on circumstances surrounding the set). If I am in very rocky ground, a ribbone just breaks up from the pounding it gets.
In locations where the ground is good enough, I think my favorite bone to use is the T-bone picked up from a bleached out cow carcass. They naturally drive in well since they are naturally pointed. Lots of dead cows in this part of the country, so not a real shortage on that type bone.
DEADLY combination at a walk-thru. Bone with call lure and then tall tuft of grass back of set with urine and/or gland lure.