The apartment is very nice indeed - roomy and quiet. There is a nice private courtyard one can also sit in and read a paper or such.
A special blessing is the train station entrance (Thorildsplan stop) is literally right around the corner - this makes travelling so much easier and after 11 hours walking around the city knowing your place is at the top of the stairs is great. Suggest getting a week long pass or more at the Pressbyran store located opposite the station entrances if you plan on travelling a lot.
Also around the corner is a nice cozy deli/bakery called Bullen - highly recommend for breakfast and lunch.
Nil's place was great to return to after a day of adventuring. It is within a 10-15 minute train ride to most places in the city a tourist would want to see. Travel tip - if going to see the Vasa go to T-Centralen then take Tram 7 on the street as the easiest way there.
Would definitely go back again - AAA+++ for us!