Well, I actually did see Orphaned Land/Katatonia last night as I am in Toronto for a week on training.
Swallow the Sun really can't compete with either of those bands, live anyhow. Their songs aren't good enough. I cheered but I was kind of meh inside. I probably would have benefited from listening to them beforehand.
Orphaned Land, on the other hand, was a hard act to follow. Kobi Farhi has an amazing voice, very clear and accurate, and Yossi Sassi Sa'aron is an animated presence onstage. Their unique melodies work very well in a live setting, plenty to sing along with and lose yourself. Headbanging moments not so much, but they do exist periodically. Kobi could probably learn a bit more stage banter, but what he did sufficed. Very fun band.
Katatonia was initially disappointing as they launched into several melancholy numbers that were a stark contrast to Orphaned Land. Neither band was very adept at working the crowd, but Katatonia even less so. However, as they started playing more from Viva Emptiness and The Great Cold Distance, things began to warm up. By the end of their set, you had nearly forgotten about Orphaned Land as you hypnotically swayed back and forth with those around you. They purposely kept their volume down, which made for some very very clear and amazing sound.
Overall, a great show.