Communication:
Sonder does not state in the listing description that their check-in process requires going to their website, which is against airbnb's rules. This by itself would be tolerable, but their website had a problem and it did not show the door code. Getting hold of a person at Sonder is an ordeal. They don't reply to airbnb messages, their phone number plays a repeated message saying they are "extremely busy", and their own app (which I had to eventually install against my wishes) has a customer support chat which no one replies to. It took me two days to get hold of someone who finally revealed the door codes on the day of check-in. That's two days I spent worrying about whether I'd have to book new accommodations last minute, which detracted from the enjoyment of my vacation.
Additionally, it irked me that Sonder's house rules (which are hidden until after booking) specify additional guest obligations and information that should be in the listing description, namely a $400 security deposit, and that "Guests are not allowed to make a reservation in their city of residence," which is an inexplicable policy to me. Additionally, the house rules state that "Sonder properties may use video surveillance in public areas. Noise detecting technology may be used inside the suite to monitor excessive noise levels." despite the listing not stating these devices, which is against airbnb rules: https://www.airbnb.com/help/article/887/what-are-airbnbs-rules-about-security-cameras-and-other-recording-devices-in-listings.
My takeaway is that their hidden conditions in the house rules and external check-in procedure make the entire booking experience feel like a bate-and-switch. In order to not lose my money and not have to rebook at the last minute, I am strong-armed into agreeing to a bunch of things that are not stated in the listing, and into giving them my personal information and installing their app. When I use airbnb, I don't want to install anyone's app. Furthermore, it is damn near impossible to talk to a human. I do not want to go through that kind of aggravation again, and I will not be staying with Sonder in the future.
The space:
This review gets two stars instead of one because the space was actually good value. The apartment is clean and stylish, and has a great view of the Willis (Sears) tower. The AC was a bit finicky and the rooms would either get very cold or very hot. Overall, it's a decent stay.