I just got back, and it was a fucking great. Three bands played: BYOP, Whirlwind Heat, and some Swedish duo called Johnossi. All three of them rocked.
The BYOP guitarist definitely jacked some moves from SY. They (and Whirlwind) ended in a sweet noise breakdown. Unfortunately, some guy jumped on stage during BYOP's breakdown and threw the bassist off. Jemina cussed him out and chased him off stage, and the guitarist followed. So after the drummer lied on his back strumming the bass for a few minutes it ended. It was great.
However, Whirlwind dominated. That was the best set I've ever seen in my life. Indescribable.
Here's a recent clip of them live. Not the one I went to but pretty similar. At one point the singer started walking around with a golfclub bag on his head. It was just really fun. Highly recommend seeing them if you get a chance.