A good article to read for food for thought on this subject is at:
http://www.lavryengineering.com/docu...ing_Theory.pdf
At this point I'm pretty firmly agreeing with Dan Lavry that the 4xFs rates (i.e. 176kHz, 192kHz) don't exhibit any sonic improvements over the 2xFs rates (88.2kHz, 96kHz) and add the inconvenience of double the storeage and more strain on the cpu if you are primarily mixing in a DAW. Personally I think that recording at 88.2kHz using the best converters you can afford is all you need to do.
Best regards,
Steve Berson