wst3
So set your budget first, set your requirements second, if they don't match start again. Audio quality is so good on all but the bottom of the barrel that it comes down to degrees of difference, or maybe even just personal taste. So if you can, listen to the candidates. And of course ask here and elsewhere about drivers and support.
 
Hard to get the best, almost as hard to go wrong... so my goal was to avoid going wrong, and stop worrying about the best... at least until the meds wear off!

Agreed almost 100% except I'd say draw up requirements first.
 
I have to say, I've tested a lot of interfaces...and I don't mean just listened to them, but did signal analysis for THD, crosstalk, signal-to-noise, phase consistency, took the units apart to see what components they were using, and a lot more. Generated a whole bunch of fancy graphs 
 
My conclusion is that no one interface hits all those sweet spots. I've found interfaces with really low distortion but relatively high crosstalk or vice-versa. I've tested preamps that people think sound fabulous but have significant second-harmonic distortion - but they might like the preamps BECAUSE of the second-harmonic distortion, not in spite of it. I've tested interfaces with great hardware and not-so-great drivers, ones with superb circuit board layouts and others with hardly any ground planes at all.
 
Fortunately, the level of technology these days is such that even the "glue" components being used are high quality. The statement "Hard to get the best, almost as hard to go wrong..." is spot on. 
 
Finally, I'm expecting announcements at AES that I think we will be exciting to Sonar users.

I didn't feel anything was wrong with my Focusrite Saffire Pro 10. Then I got my RME Babyface as a portable alternative and saw the light...

It's just a new feeling of solidity and dependability! No hidden buffers, no nonsense. RME is probably the pro audio manufacturer I hold in the highest regard. No talk of audio voodoo or esoterism, just plain old fuctionality!

My mate has a tascam uh7000 it sounds heavenly but the latency is far from great and the drivers are a bit lacking the the options department. For instance you cannot even change the samplerate from the driver panel.
 
He also has a fireface (800 I think) which is better in terms of latency and drivers but not as nice sounding, although its splitting hairs really.

+1 for the Octa Capture.  It has always worked well for me, plus I can interface it with my VS 100.