Easy Livin:
I'm an even older man! I've seen all of the following, in NYC:
Every Gentle Giant concert from 1974 onward.
Every Genesis concert from Trick onward. (Never got to see them with Gabriel.)
Every Yes concert from Tales onward.
Every King Crimson concert from "Red" through "Three of a Perfect Pair," plus the most recent tour.
Pink Floyd - "Animals," "The Wall," two others
Wakeman - "Myths" Tour
Moody Blues - "Octave" Tour
U.K. - "U.K." tour
Jethro Tull - (whichever show the "second" U.K. opened for)
Brand X - "Moroccan Roll" Tour (w/Collins)
Bruford - debut and second album tours; also w/Earthworks in 2003
The Church - "Holograms of Baal," "After Everything Now This" and "Forget Yourself" Tours
Nektar - "Recycled" and "Prodigal Son" Tours
Supertramp - "Crime" Tour
Zappa - 1977, 1978 (annual Halloween shows)
Mahavishnu Orchestra - 1975 (w/Narada Michael Walden on drums). (This was a private concert for the children of the faculty of Adelphi University; only 200 people attended. "Awesome" doesn't begin to describe it).
Other Non-Prog Faves:
Bob Marley and the Wailers (1975)
10CC (1975, 1977, 1978)
Return to Forever (1975)
Queen - "Night at the Opera" Tour
Led Zep - "Physical Graffiti" and "Presence" Tours
Santana (1975)
Elton - Every concert from his first (1970) through 1981.
Steve Miller - "Fly Like an Eagle" Tour
Police/U2/Gabriel - Conspiracy of Hope Tour
Oregon - various (over 25 shows)
Plus various shows by The Allman Brothers, Blue Oyster Cult, Joe Cocker, Grateful Dead, Bob Dylan, Hot Tuna, Billy Joel, Paul McCartney, Joni Mitchell, and many others.
All told, I've probably seen well over 400 concerts since 1971.
Peace.