I went from a 500 to 800. The 800 definitely creates a draft in the room. Not too sure it "punches" more the way you want it (upper lower frequencies you like so much if my memory serves me right, like 50-60hz). Definitely amazing feeling of "reality" when used with pipe organ, cellos or very low frequency percussion. Some of the bass extensions might be out of the audible range, but it decidedly adds a "tactile" dimension that is often only felt in an actual church or large concert hall.
The 800 shines the most with surround SACDs because of that touch of added realism.
Additional: And with movies with lots of LFE, of course!

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