Its been a while since I've gone to XS but I swear that this place never fails!
I'd say that XS has the best night swim experience! During the summer time they have a night swim on Sundays. My most recent experience was to go see Skrillex on their opening night. They have giant floaties and the water is warm. The pool is good in size and it doesn't get over crowded from my last experience. Gotta go to these night swims! It's better than being in vegas hot weather for those beach clubs without any shade and getting sunburned if you have no bottle service. BOO for sunburns!
My more recent trip to XS, we had a table going into see RL Grimes. The crowd is always welcoming. I'd suggest if you want somewhere to sit to pick up bottle service. But otherwise XS is one of the better clubs and one of my favorites behind Light. The decor behind the bar consist of bodies of women. Also, I don't get stepped on so badly at this club either because its roomy enough.