Mojo - I am beginning to think you are nuts.
LOL! You just figured that out?
When I first got my 800v4, it was a game-changer. It totally filled my 4200 cu ft room and still does. In fact, I was telling folks its good to 15,000 cubic feet. It shakes the whole house and attached garage. And its smooth and transparent for music.
But I had to go further and try 500s off my active DSPs. As I reported after I dialed everything in, I got additional 3D texturing to my bass. It's not subtle. It's so damned good!
I am glad to hear you're satisfied with your ported 600. As for mine, Axiom tried everything including Tom Cumberland calling me on a Saturday when he should have been fishing and poor Ian flying across the country with a new amp and so did I including stuffing pillows in its maw. I won't say more because you like it and that is all that counts.
No complaints with v4 though. Audio Nirvana!