We have exchanged into a 1-BR at Manhattan 2x, and a studio at Hilton Club (not W 57th St) once, back in the day when the latter was possible thru RCI weeks.
Hilton Club was more luxurious, and tho there wasn't a kitchen as I recall, at the time RCI exchangers were eligible for the free brunch and the free late-afternoon hors d'oeuvres offerings. The food was really excellent, and provided most of our sustenance during our stay! Plus there was no daily housekeeping charge, as there is at MC thru RCI, which amounts to a couple hundred dollars.
So given a choice (which I'm not), I'd take Hilton Club again over MC for 2 people, especially if the buffets were still included for exchangers, which they may not be.
OTOH, at MC we could have additional overnite guests (which we did once), and dinner guests, and 2 bathrooms, and both times we had a view of Central Park.
Both are great properties and would return in a heartbeat.
I walked into the lobby at W. 57th St once, and asked to see a room, which I wasn't able to do. The lobby didn't wow me, fwiw. I once had a confirmed exchange there thru RCI weeks, which I ended up cancelling due to a change in plans.
What are your other options besides MC?