I'll put the Hard Rock's in the mix. As a regular treadmill visitor, I've seen my share of hotel gyms in Las Vegas. Hard Rock has a very nice facility. Interestingly enough this week though, they cleared the entire room out and turned it into the AVN conference headquarters. http://www.hardrockhotel.com/relax/fitness-center
I've seen smith machines in all the big hotel gyms (e.g. MGM, Aria, Bellagio) and those are typical in hotel gyms in general. Forget them though. Monte Carlo has a power rack, complete with olympic bars and plates, the only gym I've seen with one. You can see it here: http://images.oyster.com/photos/fitness-center-monte-carlo-resort-casino-v219368-1280.jpg If you're a lifter the gyms at the nicest hotels are similar to nice gyms away from the hotels, not really for lifters and full of useless equipment. Monte Carlo is one of the only hotels I've seen anywhere that has a rack.
You're right, there is no dedicated bench press but with the power rack and bench you can do the same thing. You can pretty much do everything inside the rack since you can adjust the clips and pull a bench in or out of it. It has plates racked along the side of the rack. You can see them here: http://www.oyster.com/las-vegas/hotels/monte-carlo-resort-and-casino/photos/fitness-center-monte-carlo-resort-casino-v219374/ A big problem is though it is a small gym and with only one rack it may be occupied when you want to use it.
As the other post said HRH is a decent gym. Decent stuff(for a hotel) and they have 2 flat benches. Flamingo is decent too, nice equipment for a hotel, has a smith. MGM and Harrahs is good for dumbells and smith. With all these shopping malls popping up im waiting for someone to try to open up a gym in one of them. It might just take off. Charge 20 a day, xx for a week, then have monthly for locals.
Hopefully Sammasseur will see this thread, he has good opinions on hotel gyms. The absolute best hotel gym, for free weights, that I have encountered is the larger gym at Canyon Ranch, Palazzo. I will add it has an incredible cardio area, actually two gyms, go to the larger of the two.
I didn't know the MC had a rack so thank you for that. I always end up going to Wand Fight Team. $25 for a months access gym only, not the best for showers or air con but it's got all the free weights and barbells you need. http://www.wandfightteam.com/ I usually stay at Cosmo or MO so it's not that far a walk, takes me 10-12 minutes from the Cosmo, it's obviously not so pleasant in July :evillaugh.
I have always been impressed with a Bellagio. Nice size and a good variety of equipment. Not impressed with Mirage, plenty Ho or Aria
I'd be incredibly surprised if you found bumper plates at any hotel gym. Most regular gyms don't have them. You can see some pics of Flamingo's gym here:http://www.oyster.com/las-vegas/hotels/flamingo-las-vegas/photos/amenities/ They have regular olympic plates but it looks like the only things to use them on are the smith machine and a curl bar. No barbells from what I can see.
The Cosmo and the Venetian and Palazzo all have 2 gyms. Also Cosmo has TechnoGym equipment and a Boxing Ring.
Ball'y has at least one bench press bench and set of barbells. http://www.oyster.com/las-vegas/hotels/ballys-las-vegas/photos/fitness-center-bally-las-vegas-v208494/ Rio seems to be big, as does Planet Hollywood.
Staying at Bellagio next week - im hoping they have a barbell bench setup NOT smith rack - I'm into Strong Lifts and need heavy compound movements we shall see...
If you're on Strong Lifts then you're pretty much out of luck, Bellagio doesn't have a bench set up, just the smith machine. No racks and not even any barbells, so you can forget about doing any big lifts. If you're training for something your best bet would be to tram over to MC and ask to use their gym since they have what you'll need, explain the situation. Otherwise just do conditioning work or take a rest week.