Integrated brand choice -- Simaudio, Hegel or Mark Levinson?

Agree with the others about the Luxman 
check them out. 

I would agree with bluorion, the 507UXii sounded beautiful when I auditioned it recently.  Smooth, powerful, and intoxicating.  It was a very hard decision when I went with the Hegel 390 instead, but I knew I would be super happy with either.

I have a Simaudio 680D Stream Dac hooked up to a Anthem-Str Integrated amp with Focal Aria 936 speakers. I know the the Simaudio cost way more than the other parts of the system but I listen to streamed music mainly. I plan on up dating the speakers at some point and maybe amp but it really sounds amazing. The source is very important too.

With Focals I'd err towards Luxman, Accuphase, Pass, Ayre.

The Belles Aria Signature integrated is available nowl; the Virtuoso integrated will still be a little while coming.

Before I purchased a Luxman 507uX MKII I also looked into the comparable Hegel model. Look at the pictures of the interior wiring of the Hegel 390 at
https://www.hegel.com/products/integrated/h390 (right above the technical specs) versus what you see after you you click on the picture of the interior wiring of the Luxman 507uX MKII (right above their Specs section) at http://www.luxman.com/product/detail.php?id=4. Draw your own conclusions.

That Hegel hides where their integrated is made is telling as well. The Hegel 390 gets great reviews, but again you’re gambling on Chinese products durability. I thought about Japanese Accuphase integrateds too, but there were local availability and pricing issues if I recall. Sounds like some other good choices have been mentioned above. Again good luck with whatever you choose.

Mike