What DAC are you using?
Do you have SACD (ovbiously not that exact title) to compare the general quality.
Using a Cullen Stage IV DL-III (PS Audio). I no longer have an SACD player, so I can't directly compare. By memory, the Cullen DAC takes well recorded Redbook CDs to the same level as what I remember of SACD (not so, obviously, with lesser-quality Redbook); the well-recorded CDs ripped to FLAC sound (to me) pretty much identical to the original CDs (I rip with EAC); the Johnny A Flac download sounds about as good as my best rips (it's a little colored - slightly dark, maybe a little bass-heavy -but pretty darn good). I haven't heard the CD to compare with. I'm pretty excited to know that I can access this type of quality download from the net, and I can't wait to explore more. So far I have only downloaded a few flack files from the internet (from the B&W Members Music downloads, and from Hdtracks).
Hope this helps.