Dear billy,
Something must have been amiss if you didn't find the VTF-3 Mk2 in extended bass mode to not play lower in comparison. Frequency response in room should be strong to 16-18Hz range in this mode, and this has been verified by every professional reviewer who has reviewed the product. In maximum output mode, mid-bass headroom should also be very good, as you can see by looking at the LFM-1 results in the 30-60Hz range. It's tough to say much more without knowing specific details about the room and the comparison.
Sincerely,