The Maestro is a great amp, but a little pricier than the Raptor. When I said elastic, I meant that, when I was listening to Dream Theater, which is a very "fast album", the response time and recovery in the speedy sections, was a tad delayed. The Orpheus, which is the King, in my opinion, of any setup, was also "trying" to catch up. When I used Jazz, or chanting music (Dead Can Dance), the Orpheus, maintains it's seat on the top of the throne, but we are talking $14K, compared to $1,200.
On the Maestro, I don't hear a hear a hump in the lower midrange/upper bass.
But the MPX3, is a different design. I owned a Supra, but it's hard to compare, because, so many notes have passed through my noggin since, then

The nice thing that I found in my review, is that with the Raptor, you hear the warmth of the tubes (analog-like) that you don't get with most solid states (harsh lines....digital-like), but I didn't get the "tubey-ness", that you get from some tube amps.
Glad to meet you in Boston.