Kajsa's place is really good for a few days in Stockholm. The location is absolutely perfect, the metro is around 3 minutes walk away, there are several supermarkets, a gym and little cafes in the area, not to mention the great walk you can take along the river! Check in and out was simple and fast. Only downside for me was not having a washing machine for my clothes but that's something that I already knew in advance, you'd have to find a place to do it if you're staying longer than a few days and need to wash your stuff.
Pros: fast internet, fully equipped kitchen, nice area, public transport, only 9 minutes to central station!