I stayed here for six nights last year.

They gave me a room on the same floor as the executive lounge which was obviously convenient but it wasn't a suite or anything.

The lounge offering was fine but nothing exceptional. I ate breakfast there and also my evening meal most evenings after returning from work (I live in China so am not so entranced by local dining experiences any more). Booze ran until late in the evening.

The hard product is good and I don't remember any service issues. I didn't use the robot to order a fresh towel. Location is good and I walked around the local area which seems quite touristy and to the Bund. The hotel has a rooftop area for views at night over Shanghai IIRC.

I moved from here to the Le Meridien for the weekend and greatly preferred my corner suite and the lounge experience in Le Meridien. The lounge is a great space at LeM and the food was a notch up from the Ren. The only other comparison I have is that old St Regis that's now a Luxury Collection called the Hongta. I thought that was ok but it's a tired old product and unless it's cheap it's not worth it.