Good morning everyone
 I'm in the market looking for these two amps to drive my Bowers 805D3.
I would like to hear opinions of some users
I have heard the Naim Nova and M33 at a dealer and have had a Hegel H160 in my home, but haven’t heard the H390.  The H160 had a ton of power, so I can only imagine what the H390 would be like. It’s most likely the most powerful and effortless sounding of the bunch.  If you have a big room and don’t like to feel limited I’d go that direction.  The Naim and NAD units will look nicer with their colorful displays but all three have excellent build quality. One big drawback on the Hegel is the lack of HDMI ARC which is a great feature if you are integrating with a TV.  As far as sound quality they are all excellent and in the same league as each other so it really comes down to two things - speaker synergy and features. I can’t comment on the former since none of the demos involved the 805s. I don’t think there is a wrong choice here for a flagship all in one streaming amp. 
Thank you very much for your answer, I think I am going to decide on Nad. With what speakers did you hear them at the dealer?
I don’t remember the brand, it was a 2 way tower which doesn’t really narrow it down much. I can say with confidence it wasn’t B&W or other distinct looking speaker makers.   I was shopping amps/streamers so wasn’t really paying attention. I told the guy that I had Dynaudio speakers, so he probably chose something with similar characteristics. 
Thanks a lot
What dynaudio model are you using? Are you happy with them?

Contour 1.8mk2. I’ve had them for over 20 years now.  I’ve used a bunch of amps over that time frame, but have never thought about changing speakers. I find that vintage Dyn’s have a natural sound that is detailed without being overly analytical, which is a must if you listen to a lot of live music, especially rock from the 60’s and 70’s. The last thing I want to think about is the quality of the recording, especially now that I typically stream everything.