I have ripped my CD's to AIFF files using iTunes on my iMac. I have done that partly because I am lazy and partly because iTunes allows me to automatically have my ripped music collection automatically synched to my iPhone as lower resolution files for use in listening to music on my car.
In some instances, I have purchased FLAC downloads of some of the same albums that I have ripped. In most cases there are minimal if any differences in sound quality between the AIFF files and the higher resolution FLAC files. When there are differences in sound quality, it appears to be due to the source being remastered versions of older albums.