IMO, with most modern, cheap condensers (no offense to the V67 or the AT) the mic preamp isn't terribly important. As long as it supplies enough phantom power, is quiet enough, and doesn't botch anything else up, there are more important things to worry about. The Mackies would be good, the M-Audios somewhat better, Joe Meek more colored, etc.
Now, when you get into dynamic mics that are sensitive to loading, mic pre's begin to matter more.