Heh... I've only seen Jesus And Mary Chain once, but it was amazing... it was during the Rollercoaster tour, in Brighton England sometime around 91ish. They were playing with Dinosaur Jr., My Bloody Valentine, Blur, and Curve. The place was essentially a high school gymnasium, packed to bursting with thousands of sweating, ecstasy-crazed British teenagers all dancing their asses off.
After the show, everyone piled out onto the streets chanting "we are the mods." Just kidding, but the rest is all true -- the only time I've ever flown across the Atlantic to see a show, and totally worth it.