My husband and I just returned from a long weekend stay at Southernmost Hotel. The room was very clean and hotel staff very friendly. We spent some time at each of the 3 pools and enjoyed them all. Live music at the pool was very enjoyable. Had a couple of meals at the hotel's cafe on the beach. Food and drinks were very good. Front desk was responsive to any request we had.
Hotel is located at the south end of the key. In the evening we would take a taxi to the north end of the key. We had dinner on the north end and we also liked the north area to watch the sunset. After dinner each night we would walk back to our hotel straight down Duval Street. It was dark out at the time of the night (10:00 - 11:00 PM) We never felt unsafe and the approx 1 1/2 mile walk was a great way to walk off a little of our dinner. Duval Street always has a lot of people on the street and on Saturday evening it was actually crowded on the street.
Morning coffee is an important start to my day, and the hotel provides coffee in the lobby. There is a great coffee shop across the street called "Frenchies" that has wonderful french pastries and coffees. Definitely schedule a visit to Frenchies if you are a coffee/pastry lover!
We were told that September is Key West's slow time of the year. I think it was a great time to spend a weekend there.
My only negative is that I was a little disappointed with the beach area. There was so much seaweed washed up on shore that it just was not very inviting to go into the water. If you are the type of person that never goes into the ocean water, you will be OK because the sand area was clean and hotel guests get free lounge chairs to use on the beach.