I think it would be very difficult for most people to tell that songs are generated by Suno 5. There are some interesting anomalies I can see in the spectrum and mid/side channels, like Suno music often has very little information in the side channel (what happens when you subtract the left and right channels from each other). You also commonly see the eq curve of the rhythm section shift over time throughout the song - like drums will sound normal at the beginning but end up sounding kind of under water by the end, but they are quickly improving these things. But to the layperson, many of these things are completely invisible. The most obvious tell, IMO, is the cadence of the lyrics.