Tried them all. Totally agree with bdp24 and daytrader. The C version was certainly a lateral move. Too many variables and never any clearly written directions. Maybe that is just me. A and B better sounding.
I have modified one of my LFT3 to make it an LFT4 for comparison. I temporarily disable the dedicated bass panel section.
My LFT6W has been built and should be in my possession by end of the month. My LFT6 is being crated for its return home. An LFT7 experience is on the horizon.