Is there anything better than the NAD 320bee

I'm not sure what your power requirements are, but the NAD c370 would be a great choice at this price point too. I got mine for less than $500 delivered (new). I have not heard the 320bee, but I really enjoy the c370. It has loads of power and functionality to spare.
As far as other brands, the only piece that comes to mind at this price I would seriously consider is the Audio Refinement Complete. Around $500-$525 used. I went with the c370 for the power, the ARC is around 50wpc.

I haven't heard them, but I've heard great things about the new Cambridge Audio Azur integrateds.

Depending on what you like, and I have owned an ancestor fo the 320, the 3020i, but I think the new Rotel RA-series amps are terrific. Perhaps less refined than the NAD (based on reading), but also punchier and with more attack and Prat. Also comes with a built-in phono stage, and looks great as well. The matching tuner and CD player are also considdered very good, and also look good. A friend of mine who works in a high-end shop bought the Rotel tuner over the Magnum Dynalab, as the sonic difference wasn't nearly so significant as the price difference. Myself, I was blown away by the Rotel RA-01 at something like $350, when it was playing over expensive Tetra speakers. I thought it was one of the most musical sounds I had ever heard from this particular high-end shop (stuffed with Hovland and so forth), and I simply can't stop thinking about it, even though I have great separates. Great macro- and micro-dynamics. And though it is very slim, it's extremely heavy: I thought it was being held down by cables or nailed down! I may buy one just for kicks. Who knows? Maybe time to sell my disjointed separates and buy an all Rotel RA-series system!