I was "lucky" enough to experience living in 2 of the Sonder properties during my Denver stay. When I arrived, I found out there was a scheduling error with the system, so the room that I had booked was currently occupied. The Sonder staff quickly made arrangements for me to stay in one of their Capitol Hill 1-bedroom apartments for the first couple weeks of my stay.
Capitol Hill:
The general layout and Capitol Hill space was very nice - similar to living in a large hotel room with a living room and kitchen and washer/dryer. The kitchen at both places that I stayed at was pretty well setup, with everything one would need for a longer stay and plans to cook meals at the apt. The WiFi in Capitol Hill didn't seem to be as strong as the WiFi at Zuni, but was manageable so long as I wasn't trying to surf on my laptop and my phone at the same time. I didn't do much walking around in the Capitol Hill area, but I did drive by some really nice houses just to the south. There's a Safeway a couple minutes north and a Trader Joe's a few minutes longer south. There were some bars and restaurants a couple blocks north, but I didn't make it over to them. There was some noise during the evenings on the weekends from the bar on Colfax. The designated parking spaces helped a lot.
Zuni
When I was able to move into this Zuni apartment for the final week of my trip, I could definitely feel the reduction in space moving from a 1-bedroom to a Studio. The amenities were very similar which was great and the WiFi was pretty consistent. The rooftop was a great perk and there were a lot of really great bars and restaurants within walking distance. If you've got a car, street parking was pretty easy to get just in front of the building or just down the block. The door locks on the apartments were a bit confusing at first - I'd never experienced the keypad that's hidden until you put your palm on it.
Advice for those looking to rent these: double-check to make sure you're booking is confirmed. My app said it was, and being in an unfamiliar city and needing to move to another side isn't the first experience you want to have. Thankfully, Sonder was able to resolve it pretty quickly.