Yes, I have an Elf system; and I love it. The low end curve is very smooth. It does seem to me that it's not very loud. I run one 18 sub off one side of a 2402, which is 425 watts into 8 ohms. When I go out I run a 4 ohm Eden 210XLT on the other side, and together, from a volume perspective, they are a good match, and fine for the gigs that we play. I have a second sub, but I haven't used both at the same time yet. My plan there would be to run them in parallel off one side of the PLX.
At home I have a Bag End D10X-D, which I think is a great sounding cabinet. I prefer it's tone over the Eden, but the Eden is louder, so that's what I take out. Perhaps the D10BX-D, being deeper in size, puts out more sound.
I believe Michael plays or played through a D10X-D on his gigs.