I loved "Dre Day" back in the days. And that's funny, because I was never a Dre fan... They made Tim Dog, Luke and Eazy-E look like bitches AND Deathrow look unstoppable in one song...
But "Real Muthaphukkin' Gs", man... If Dre slapped Eazy, Eazy went back and beat his ass to death. Eazy, bg knocc-out and Dresta all kicked classic verses.
Then of course "Hit 'Em Up", for all the reasons mentioned... It was the shit.
Also... E-40's diss to AZ was dope... Spice 1's "You Done Fucked Up" was cool... DJ Quik's diss to MC Eith, I think it was called "Dollars & Sense" or something like that... and many others that I can't think of right now.
To me you see a diss song is great when you feel it even though it disses a rapper you like.