I don't think that the Plus will have worse distortion measurements than the EX, if anything, better. I believe it is using the same driver, and that driver will not be pulling off as much excursion which the EX will put it through, so it should stay cleaner. Outlaw claims that the Plus performs similar to the EX except 4 dB down, although I wouldn't guess that would hold across the board. There is no question that the LFM Plus driver will be a higher performer than the PB1000, it has 30% more cone area and almost certainly greater xmax. Sure the Plus would have more output, but, from looking at that THD chart in the PB1000 review, I think it will stay a lot cleaner for the same output sweeps as well.