FM/AM versus Analog versus Digital

Not really comparable when you think about it. All your tuner is doing is receiving a signal from a radio station using a CD player or analog turntable. The sound you are hearing is created primarily by the CDP or turntable in the studio and transmitted over the airwaves to your tuner. A high quality, uncompressed, signal fed to a very high quality tuner will come very close to replicating the sound of the CDP or turntable used in the studio. If you have the same CDP or turntable at home your's should sound better.

FM is also bandwidth limited, I think, so it won't give you the full frequency range you can get from your other front-end components (although those with limited frequency response from their speakers may not care about this). And among Newbee's excellent points is the kicker, an UNCOMPRESSED signal--sadly, very few radio stations send this out. Very noticeable on large scale orchestral works, where the loud parts are usually mercilessly squashed in order to be broadcast over the airwaves. With pop stations, which routinely overmodulate anyway and most of the recordings have a compressed dynamic range to begin with, this is less noticeable. Despite all that, if you can get a live broadcast over a good tuner, it is frighteningly good.

Two very good replies, nothing to add except to wonder why the poster places so little thought for digital.