The way I look at it is this. In 1984, Yes was on the 90125 tour, and a few peeps didn't go to the show because that lineup didn't include Steve Howe (who was in Asia at the time). I went, and I can tell you that it was absolutely phenomenal. As I sit here, 30 years later, I'm sure glad I didn't decide not to go because Steve Howe wasn't there.
Just sayin. I also had people suggest that it was a waste of time to see the Rolling Stones in 1989 on the Steel Wheels tour, since they were "washed up". Ditto AC/DC on The Razor's Edge tour. Both concerts were fabulous.
Bottom line, if you've an incline to go, and have the time and money, I'd do it.