Brandon - The EP800 works incredibly well with a variety of speakers. There are 3 EP800's here, and I have actually run a pair with a VP150 and a pair of M3's, and everyone who heard the system was astonished.
A lot of this comes down to your ultimate budget.
I can tell you that once you experience an EP800 in your system, you will not want anything less. In the Outlet, the M80's are $1040 less than the M100's. The EP800 is $2480 ... so it would be a net $1440 more for M80's/EP800 than a pair of M100's.
The question only you can answer is how important is that $1440 in your purchase decision?
In regards to the Hsu ... "30%" is just where the gain control is. It does not mean you are only using 30 percent of the unit's ability to deliver SPL.
A pair of M100's and a VP180 would be a large step up ... and you could easily run them as large, with the Hsu augmenting the deep bass, and have one terrific system. Maybe, if you need more bass, you can add it later.
