I haven't been to many live gigs, unfortunately, but I did see these at Donnington/Download this year and last year:
Korn
Def Leppard
Thin Lizzy
AC/DC
Megadeth
Slash
Rage Against the Machine
Killswitch Engage
Motorhead (only a bit)
They were all great, but I'd say AC/DC and Megadeth were the best; Slash, Thin Lizzy and Rage Against the Machine, too.
Korn
Def Leppard
Thin Lizzy
AC/DC
Megadeth
Slash
Rage Against the Machine
Killswitch Engage
Motorhead (only a bit)
They were all great, but I'd say AC/DC and Megadeth were the best; Slash, Thin Lizzy and Rage Against the Machine, too.