Welcome to the forum!
What is the room size?
I have an older VTF-3, and just recently got a used STF-2. The STF-2 gives up nothing but the deepest notes to my VTF-3. The new VTF-3MK2 has a more powerful amp and should have more authority on bass peaks.
My room is 14x18 with a sloping ceiling from 8 to 9ft, one uncloseable doorway into the kitchen.
-curtis