Apartment-like Suites with a Great Location
We got a wonderful deal through Jetsetter at The Alex, and I would definitely return. The rooms are really like apartments that many Manhattanites would be jealous of. We had a spacious living/dining area, multiple closets, bedroom, hallway, bathroom and kitchenette which featured a stovetop, dishwasher, fridge/freezer and utensils as well as pots, pans and dishes. Therefore if you are looking to stay a week or more in NYC, I highly recommend it. 
Other things I liked: the Philosophy bath products, lots of natural light, the flatscreen in the bathroom and the location. There are many restaurants and bars around, plus it's right near Grand Central Station. Since you have the kitchen amenities, I suggest going over to Grand Central Marketplace.
There are only two things that turned me off during the stay. The first was the overzealous bell hop who explained EVERYTHING in our room in great detail. I'm sure he was only doing what he was told, but you don't have a choice as far as the bell hop - they take your bags no matter what and then proceed with a long tour of the suite where they even explain how to use the dry cleaning service. 
The second annoyance was housekeeping knocking on our door on Sunday morning. Since we were checking out that morning, they should have been able to see that we did not check out yet - why did they have to bother us before 9:00 a.m. on a Sunday? 
Those two things aside, I would definitely come back here for an extended NYC stay.