SLS is my favorite hotel in Las Vegas! I stay there whenever I'm in town for work and I am more and more impressed with the friendly staff throughout the hotel, especially Katrina at the front desk. I also LOVE the rooms in the Luxe Tower. (I do agree with comments that one tower is a poor attempt at a remodel of the old Sahara rooms - just be sure to ask for the Luxe or World Tower when you stay and try to avoid the rooms that face the parking garage.)
Definitely a hipster hotel that appeals to the Millennials but I think the combination of "new" music playing throughout the property and the tribute to the "old" Sahara visually with the graphics in the carpet and on the walls is creative. (Be sure to look up, down and all around at SLS or you'll miss what this place is all about.)
There is a very cool photo gallery that is a little tough but very worth a visit. Cool pics of rock legends and movie icons. (They are for sale but way out of my budget.) :)