Bob, I pretty much stick to baby backs these days. But, if I smoke spare ribs, I buy the 3-rack pack from Sam's. These are untrimmed, full spare ribs. Not sure what a KC cut is, but I don't cut the tips off to make them St Louis-style. I actually made a mistake in my post title, by calling these St Louis spares.
I think the tips are the best part of spares!