When considering the type antenna needed, only the "real" channel is relevant. Virtual channel numbers tell you nothing about the frequency used to broadcast the signal.
The 91XG is one of the highest performing UHF antennas available. However, it's only designed to receive UHF channels 14 and up. In some applications enough VHF signal will be received to be usable, that does not make it a fist choice for VHF applications though.
If I were in your situation I would choose to install two or more antennas aimed in opposite directions. I combine UHF and VHF at the RF level with a UVSJ. But I have all signals available to my computer based receivers using network attached tuners.
http://forum.tvfool.com/showthread.php?t=820
In your earlier threads, viable suggestions were offered regarding antenna choices. All of the viable antennas suggested are large deep fringe designs, either single combos or separate UHF and VHF combined at a preamp.