In the area of The HOB, where the concerts, and parties are held, there isn't any seating, except for VIP, and you're lucky to get into the VIP section, you'll be treated to a bench.
However there are about 15 bar stools upstairs, so if you're in that lucky first 15, you can have one, other than that, you're standing, shoulder to shoulder, back to stomach, the entire time you're there.
Yes, you will be able to get in if you have a ticket, but again, it's standing room only, so if you're late getting there, you will be in the back of the spot, which is not big, but that's where all of the people trying to go back, and forth of each side of the club will be, which will mean you won't see the show you paid for.
Good Luck.
NICE