Well, I'm glad you resurrected this thread. In the first place, nobody answered Miguel's question above. In the second place, transponders 17, 19, 21, and 23 may in the future be placed into spotbeam mode, though my receiver doesn't say "spotbeam" as yet. Nevertheless, we're seeing a pattern on the ground consistent with spotbeams right now.
Transponders 17 and 19 (and 21 and 23) all went down dramatically in signal strength a week or more ago for me. My own spotbeam (tp 13) reads 75-81 here in northern VA. But the others listed above, which may in the future be put into spotbeam mode, all hover around half that: 25-30. IMHO 40-47 is usable, but you probably need to get your dish peaked.
Of course Miguel is getting nothing in Puerto Rico.