Hattor Ultimate Power Amplifiers


I am wondering if anyone has tried Hattor Ultimate Power Amplifiers? I am currently driving Martin Logan ESL X speakers with a pair of Nuprime STA 9s as mono blocks. I am happy mostly with the soundstage and detail I am getting,  but I am experiencing a little harshness at very high volume and I am wondering if next level class d will afford more musicality and punch. Anyone with experience going up the food chain in class D amplifiers have any insight on this? Thanks,  Tom

System:
Rega RP8 with Apheta 2 cart
Rega Aria V2
Khozmo (mostly) passive preamp
STA 9 monoblocks 
ML ESL X speakers 
128x128tomflynn
Thanks guys. I managed to borrow a Son of Ampzilla 2 from a friend. And just coming out the gate, barely warmed up, it is clear that stepping away from the Class D monoblocks is my direction.  
By the way, I am thrilled with my Khozmo mostly passive preamp. Arek added a simple stepped  attenuator to it for me because I needed a little more gain in my system.  Arek at Khozmo was a delight to do business with also, just awesome customer service. I have had other serious preamps in my system, from Berning to Superphon,  and this Khozmo is my keeper. It is so clean and simple and it lets the music bloom. My original post was really about whether or not to go Upstream to the $3K to $5K class D amplifier level... and for now i have made my decision... A/B.
Class D is not an optimum match for electrostatics.
middlemass and  mijostyn are correct tomflynn OP , Class-D really dislike driving 1 ohm loadings in the highs, and that is what the Martin Logan ESL’s present, and a heavy negative phase angle –68.81º at 5.9 kHz together with 4ohms loading.

Cheers George
Underwood HiFi has a few Ampzilla amps/pres at great prices

Ampzilla 2000 Mk II for $5995 the pair

Select Specials and scroll down

hth