I saw YES at the Mala Sportovni Hala in Prague. They hit the stage right around 8 and played for over two and a half hours. Among the older stuff they played was America, Long Distance Runaround, Roundabout, Starship Trooper. The crowd seemed really pleased with some newer stuff-- Owner of a Lonely Heart, etc.
Steve Howe did a long acoustic set, and blamed the arena ice for driving his guitar out of tune, but the set didn't suffer so much from it. The lighting design was top notch, and the sound just slightly muddied by the less than ideal stadium conditions.