Winamp is a popular FLAC music player for Mac supports numerous audio and video formats.
You can also look for its reviews here, on head-fi, for eaxmple:When you want to enjoy the FLAC music files with the original quality, what are the best FLAC players for Windows, Mac, Android phone and iPhone? FLAC stands for free lossless audio codec, which retains all the audio information while it compresses a big file to create the smaller file. So, if I were to use 10 point scale, Sansa clip would score 10/10 for reliability, 10/10 for mobility, 8/10 for functionality, 7/10 for user menu, 6.5/10 for sound quality. You can also try to get one of such players cheaply secondhand, that's what I did, as I wasn't sure if I would like it, so I got mine for about 15 quid ($20) used, and It works with no problems at all third year straight, while other players that I own during same period, either broke down or died totally.
It is not the best possible and friendliest, but comparing to other players, it is alright. You can group your music in folders, order them as you like, create playlists, etc. Sansa menu is quite user-friendly and intuitive, as for such a small device without graphic user interface nor touchscreen.