If you are going for a stag do, you might not want to go for the nicest hotel necessarily.
The Mrs and I stayed in Paris when we went - lovely hotel, directly opposite the Bellagio so a great location, but quite pricey and not quite so wild as some of the other places.
If I was going for a lads trip, I'd go for somewhere cheaper and save the cash for other purposes (err gambling obviously). After all, how much time are you going to actually spend in the room? And will you be sober or awake when you are in the room!?
That said, Mandalay Bay is a bit isolated but is apparently teeming with young singles so might be a good stag do base. I also have it on good authority that Hard Rock hotel has some sights to behold.
If you want a really nice hotel in a good location, also consider The Venetian. It's amazing!
The Mrs and I also thought TI (previously Treasure Island) had a really good atmosphere.
Oh boy, just writing this makes me want to go back.....
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