I'm surprised to see so many lukewarm reviews of Beacher's Madhouse! My friends and I had an amazing time. We first tried to get in to Hakkasan, but due to miscommunication with a promoter we ended up choosing to not wait in line (I think Calvin Harris might've been playing so it was a 3 hour wait, $60 cover, no thanks). As we walked by Beacher's Madhouse a promoter offered us free entry and a free drink, so we decided to check it out.
The bar itself wasn't the nicest - I can see how other reviewers felt disappointed by the bottle service areas. However, they played AMAZING music - top 40/hip hop/way back playbacks and it was such a fun atmosphere. Everything from Kendrick Lamar to Drake to Beyonce, etc. which was a nice change from the typical Vegas club music. People were dancing on tables, watching midgets perform - they were dressed like Bon Jovi, Beyonce, Lady Gaga, and I couldn't take my eyes off of them. Occasionally they would fly overhead on a wire to deliver bottles. Plus there were characters like Elmo and Big Bird dancing around, so the whole place was just a random, fun, bar/club experience.
If you're looking for a laid back, fun time, definitely check out Beacher's Madhouse!