I have used MediaMonkey, Foobar, Windows Media Player, and some others (XBMC, WinAmp) briefly on W7, mostly with lossless flac or wma and find no differences whatsoever in SQ (if properly set up, do no digital effects, volume 100%, balance halfway) using USB DAC. MediaMonkey is easiest to use out of the box, imho, new version coming up soon they say.
Problems can arise (interruptions) due to bad drivers in your system, background operations and update downloads etc, but in general it works fine. Including gapless playback that some expensive dedicated mediaplayers do not master, so I have learned to my surprise. All are free, at least in some versions, so you can try for yourself. Biggest differences are in management of the collection, tagging, options for remote controllers, dlna options, but for playing they all work fine.