Need a DAC recommendation

It has been my experience that there isn't a great deal of information out there regarding the performance of all the new DACs coming out--especially for more affordable ones.

I need a new DAC and I'd like to spend less than 600 used or new, the cheaper the better. USB would be nice, but I'm probably going to use digital coax mostly from my computer. I only listen to FLAC and I always try to obtain the highest bitrates possible, so the DAC has to be able to accept at least 24/96 (192 or higher would be even nicer, as would upsampling, but I'll take what I can get for the price). On my other system, I have a V-DAC with the V-Link usb/spdif converter and its not bad. Any advice would be greatly appreciated. BTW--Anyone try the VDAC II?
Since this is a technology that changes rapidly, and we already have the ability to make DACs that can achieve much higher bitrates, I was hoping that there is, or will be, a great new generation of affordable DACs on the market. Seems to me that the majority of DACs on the market are a bit obsolete Months ago, I saw buzz about an exciting DAC from Asus:
Upsamples to 32 bit/352.8Khz and is only supposed to cost about $250-$300. Now, I realize that Asus isn't the prototypical audiophile company, but they make a good soundcard, and maybe at this point it'll take a computer electronics company like Asus to make something that renders the competition obsolete at a fraction of the price. Unfortunately, there's been no news of this DAC since then. Anyone know of anything on the market that can achieve upsampled bitrates higher than 192 for anywhere near that price? Also, does anyone have any experience with the HRT streamers? I wish there were more current DAC reviews out there, but I can't seem to find that many.
I would like argue the importance of the overall design of a DAC, such implementation of the output stage (opamps, tube, discrete fets)and power the supply, which some say is more important than the dac chips and bit rates.

However, taking this 180 degrees, I'm blown away by the performance of my $150 HRT Music Streamer II (after 300 hour burn-in).... which uses cheap opamps but asynchronous USB technology... I think that the $350 HRT II+ should be on your shortlist if USB is all you need.
Funny, I would recommend a several much older DACs that have great analog performance, quality power supplies but not the "latest and (supposedly) greatest" chipsets.

My experience with most of these mid price latest/greatest chipsets is that sure, they up the bit rate, but in the end don't sound as good!

My recommendations would be a CAL (California Audio Labs) Alpha tubed DAC (preferably, since you care, the 24/96 version). These are typically around $500, but usually sell almost instantly when they do list.

Another strong recommendation would be the Kora Hermes (which does upsample) and is also a tubed DAC. This may be just above your price range, but will kill (based on those I have listened to) of the current 7 pound latest chipset dacs.

I have had some great DACs, including DCS, EMM Labs, Esoteric and others. I can tell you that these are great dacs even running at 16/44 absolutely kill these latest/greatest DACs (running 24/192 etc.). Remember, at some point the DAC needs to send an analog signal. Doing this well requires a good analog circuit design and componentry (HQ parts) and a good power supply (like in a preamp). Good power supplies cost money and have good weight to them. The best chipset in the world can't make up for a bad power supply and analog circuitry (take a look at all the HT Receivers with super high "bit rate" upsampling). They still sound like crap.

My point, you can go for super high bit rates, but this won't guarantee (or frequently deliver) better performance if the other issues (which are just as important) are not addressed.
Agreed, the importance of the Analog circuit and quality of components is crucial. But in the terms of value, digital has come a long way when we look at sub $600 category (i.e. this thread), and the $150 HRT Streamer in my office system smokes my old Cal Audio DX-1 (a $600 player in 1994)in terms of resolution and soundstage. I think, too, that the current technology does a lot better job addressing jitter.