We visited to celebrate my GF's 30th birthday. It was her first trip to Las Vegas, I've been plenty. We chose a 1 bedroom terrace at Cosmo because the hotel is newer/stylish and VERY CENTRAL. The room is higher end Vegas w/ a nice kitchenette, cool shower/tub view, and a TERRACE. All bonuses in my experience.
The public spaces in the hotel were cool. The hotel is decorated "fashionably". The Casino space is hip and the Crown jewel Chandelier Bar was beautiful. We toured the entire strip, taking in the sights of Chinese New Year decorations. Being able to walk out of The Cosmopolitan and right onto the strip is a huge plus. Turn left you can go straight into Bellagio. Go straight and you're in Paris. I hate the detours of the over the road sidewalks, so as I said the location of this hotel was a plus. If you're taking a taxi to the North outlets it's about $18, Fashion mall around the same.
I made a few requests for my reservation (wine glasses etc.) that weren't fulfilled. Not the end of the world. A friend of ours sent Champagne and strawberries to our room. He mentioned it took a few phone calls and emails to arrange it (slightly annoying). I wanted this hotel to be my new favorite on the strip. It could have been. It was close. Above and beyond service would have been the difference. If you haven't stayed here try it. But I still prefer (1)Bellagio,(2)Wynn,(3)Aria.