Ive never seen a foriegn musician live.Unless you include those guitar players in the London underground,who are pretty awesome btw
Ive only seen footage of major bands.Based on that footage,id have to go with Kiss and Guns N Roses.I havent seen a lot of Led Zeppelin live footage,but ive heard that they were extremley unpredictable.On some nights they could blow the roof away,and on other nights they could fall flat.
Ive gone for Kiss because of the visual aspect.Kiss on stage just wasnt a concert,it was much more.It was like a movie and music show rolled into one.The same goes for Pink Floyd.While Pink Floyd's music is big enough to survive without the effects n stuff,but that probably wouldnt happen with Kiss.The visual aspect of Kiss had a huge role in making them the stars that they were.
Guns n Roses because of the energy Axl had on stage.I dont think any vocalist,other than David Lee Roth perhaps,had the same onstage energy as Axl.His vocals never seemed to suffer no matter what he did on stage.Guns n Roses as a band were obviously insanely explosive,and that translated into something larger than life on stage.The amazing thing is that unlike a lot of 80's band,GnR never relied on pyrotechnics,fancy laser shows etc.It was all raw agression,and when it clicked..it was phenomenal.