Ive stayed in LV 7 times now, always at IP.

First time I stayed, I chose it as the cheapest advertised for that point on the strip. I played 'serious' roulette for several hours that trip, relieving them of $2k. That night, an envelope containing a platinum vip players card was pushed under my room door.
On subsequent trips, I would phone to book the room, quoting the card#. Room was either free or close to. When I went to check out I would present the card, and got a rebate off room service, phone etc. I never gambled there again except a few $$ here and there. I got 5 'cheap' stays out of them although as I said elsewhere, the main reason I stayed there was that I could park the car 50 feet from my room and get in and out quick. On my last visit they wanted to charge me full rate. I argued it down to a players rate but by the time I add food costs, it was no cheaper than anywhere else

As people have said in the past, the buffet sucks and the restaurants are 'so-so'. Room service food is good but at a price. Unless its a special occassion I tend to eat fast food in LV. I have to suffer the elevators and 20 minutes crowd jostling to get that hence I use room service.