What SS Dac , Bel Canto,Benchmark, ?????

I am looking to get a SS Dac for my system,currently have a Cal Sigma 2 ,would like to firm up the Bass and add better highs.My system consists of B&K avr307 receiver,Sony 222es cd player used as a transport and vandersteen 3A speakers.Thinking of a Bel Canto Dac2 or a Benchmark dac1,any other suggestions? My budget is about $700.00 max new or used is fine.
If you get a Benchmark, which is a good choice IMO, you should make sure it is a recent one. They have undergone a lot of improvements over the last 2 years. It is mostly surface-mount, and AC-coupled, so these are the weaknesses IMO. There is not much stock that would make me happy. Even the Dodson 218 at $8K does not ring my chimes....
Steve(Audioengr) forgot to introduce himself as a modder. His company is Empirical Audio that does mods to Benchmark, Bel Canto and number of dacs and transports and they are pretty good....I heard several of his mods and they sounded good, but that's not the answer to your question. In any case, Benchmark sounded too cold and sterile in my system comparing to Bel Canto DAC2. Bass was better on Bel Canto and detail was smoother. I thouhgt the Benchmark sounded too digital. It was more of what it is - a recording monitoring tool. I sent the Benchmark back and kept the Bel Canto, which I enjoyed for about a year until I bought the ARC CD3MkII player and even then Bel Canto dac was not embarrased completely. Very good performer and an excellent value. Just my $.02
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The more recent Benchmark dacs from about the last 6 months do not have the harshness of older units. I had the Bel Canto Dac in my system some time ago, and while my sonic memory isn't perfect, the Benchmark is much more resolving with lots more low level detail and better bass. Of course, YMMV.

Any idea how to differentiate between the revised and older units? The face plate of the older units are larger than the revised ones? Or we can tell from the serial numbers?

Thanks in advance.