Not really a huge fan of the Grateful Dead but my best friend was and in college, well we saw them quite a bit.
Hard to top a Yes concert if the sound is good just because they are very talented but I get that they are not for everyone.
I have to say that most of the concerts I've been a little disappointed in. I saw REM in concert, one of my favorite bands, and left disliking them. But some of their early stuff I still really like. Like Michael Stype or not the guy is very gifted lyrically.
FWIW, I want to see Tool play (and they are in May locally). Another collection of really good musicians. The music can be a little too dark and heavy for me but again, the talent thing is almost to much to pass up. I am also a huge Maynard fan in general. But I have passed up opportunities to see him with Puscifer and A Perfect Circle... but Tool? Part of me is telling me I'd be stupid not to, lol
If Page Plant and Jones had toured as Zeppelin, even now, I would have gone... no matter the cost... which would be steep. I can only guess at the price of an average ticket. Tool is going for about $200 a ticket so I am guessing it would be more than that.