I was lucky enough to see Genesis first in 1980 on the Duke tour, but at the time I can remember thinking I was 7 or 8 years too late. When I saw Gabriel in 2004 a couple of young guys we met were extremely envious that we'd seen them so "early on"! So it's all a matter of perspective. But just out of interest I'd love to know who saw them first and where? Anybody at the Marquee in 72 or the Reading festival 73?
First Show was the Lamb, Newcastle City Hall, April 1975. Great to see the slide show on the box set. Brings back memories. Also saw PG and SH's first solo tours. Yep, I'm old.
I joined about the same time as Daryl, just in time for the ATTWT tour, which took Genesis to Knebworth for the smoke and mirrors show in June 1978. Apart from making the mistake of queueing all night to try to buy tickets (that had all been sold to the fan club) for the Duke tour at Hammersmith Odeon, I have seen at least one show from every tour since, even CAS!
I really wish I'd seen them on the ATOTT and W&W tours, but as I said during my filmed interview outside Kensington Odeon, I was far too young... :-)