We had a 5 day stay in October with 5 people.
Pros:
plenty of space for 5 of us, would be totally fine for 8
good communication
easy check-in / check-out
Internet worked throughout
location was OK (30 min to center of Milan via bus), it will be great when the new metro opens
rooftop terrace
Cons:
no smoking allowed anymore, but deep smell of cigarettes
stairs to the basement lead up to a wall you have to step around onto stairs coming down from above (tough for those with reduced mobility / balance)
the 2 modern bathrooms are both in the basement with 1 bedroom, the other 3 bedrooms are upstairs with only the green bathroom
only the bare minimum of amenities provided like towels, TP, detergent, soap, etc. (there's a grocery store right around the corner to re-stock)
2 of the beds weren't made up
could be cleaner in the details (wall stains, mildew in corners, etc)