I stayed at
Monte Carlo and had no problem with thin walls. In further conversations with others who've stayed there, we think it may have something to do with the number of mudslides I consume in Vegas--normally I'm a very light sleeper but I had no problem sleeping through the night in our
Monte Carlo room. Further--our friends were in the room next door to us and stayed out late clubbing--we never heard them getting in late at night, and they didn't hear us leaving for breakfast early in the morning

The plumbing IS loud, but I only heard our plumbing, not the neighbor's. I had a LOVELY time at Monte Carlo. Alas, I cannot compare to your other choices since I haven't stayed at
Mirage or
Ballys. If the choice were mine, it would come down to the price available during my stay--if
Mirage were the same price as the other two, I would choose it. Between
Monte Carlo and
Ballys at the same price, I would choose MC because I have a better vibe in the casino there, but "vibe" is one of those indefinable things and completely personal.
Ballys does have a good location, but I don't think that the
Mirage or
Monte Carlo have a BAD location. Good luck with that choice!!
PS for Monte Carlo: you can request a refrigerator from housekeeping when you arrive. If one is available, they'll bring it to your room--they're free, but first-come, first served.
Monte Carlo is next door to a new CVS drug store (gee, I guess it's a couple years old by now

) and it's a great place to stock up on water & soft drinks to keep in your fridge, sunscreen if you forget it, and even decent priced post cards and other Vegas souvenirs (in our house, we call them "trinkets & beads" no matter what we're buying

)
[ March 22, 2004, 12:22 PM: Message edited by: HoyaHeel ]