I've stayed at the Ren North Shore on many occasions. In fact, it is the first place I look rather than staying downtown. They are undergoing a big lobby renovation but the rooms are totally done and the CL is done. Speaking of CL, it is stellar and Elizabeth, the attendant, is so awesome....she ranks up there as one of the top Concierges in the Marriott system, IMO. She bends over backwards for every person walking through the door and if you stay a few times, she knows your name and remembers it no matter how long it is between your stays.
Rooms are nice and comfortable, never tried the restaurant but there are plenty of places nearby to eat. Also, Northbrook has some of the best shopping so if you have money to burn, you can certainly do it at the mall and surrounding shopping centers. Make sure to check out the Prairie Grass Cafe just up the street.
Book the Ren, IMO-I think you would enjoy it.