The rooms aren't 5 star, so let's get that out there right off the bat. But the services are outstanding. Toursim in India is singularly phenomenal, but also exhausting. I recommend you treat yourself to just one night at The Oberoi so that you can avail yourself of the swimming pools (one indoor and one outdoor) and the spa, which is only available to guests. I had a an ayurvedic oil massage that was excellent. First they told me my dosha (it was kind of a quick survey, so not sure how medically sound the determination was, but whatever) and then they made up an oil to suit that dosha and used it for my massage. Outstanding.
Dinner can be at one of several restaurants. We ate Thai and Indian food at The 360 on the lobby level. It was good atmosphere, not too formal, not too casual, and while it is not the best Thai food I've ever had, it was very good. My husband said his Tandoori chicken, made in the Tandoori oven you can see from where you are seated, was excellent. He asked for a combination not on the menu, and they were happy to oblige.
But so as not to have you go there only to be disappointed in the room, let me explain that: It isn't 5 star. It's adequate. It's even nice. But it's just not "all that" so set your expectations and you'll be fine.
Go for the pools, the tranquility, and the spa. It's a quiet place in an otherwise overwhelmingly hectic city.