I booked this studio for one night in the Korte Janstraat in Utrecht which is in the heart of Utrecht and a 10 min walk to the Central Station and a short walk to numerous bars and restaurants.
Since it was a studio, I had to collect the key since there is no reception desk in the building. For me personally this was a bit inconvenient since I had a meeting till late in the evening so had to collect the key during one of my breaks. I was aware of this and the owner was very helpful in setting an exact time to collect so not that big of a problem. There is no toilet in the room but there's one in the hallway a few steps away so for me not a problem either. The studio is well equiped with a little kitchen, nice shower, closet, TV, little table with chairs and nice comfortable bed. The only real downside was the fact that this appartment was really noisy even during the night ( was staying there during the week, so not even during the weekend ) The studio was located streetside and when a group of people went by, you could almost follow their conversation ( with all the windows closed ). So, if you're a light sleeper I wouldn't recommend staying here. Other than that it was an enjoyable stay.

In January 2011 I stayed for one week in one of the Havaa apartments at the Plompetorengracht, and enjoyed my stay.
The location was perfect as I had to go daily to the Jaarbeurs, and it took me only about 20 minutes walking to get there.
The apartment was very clean, and has everything you need, even in the smallest details. The on property manager was very welcoming, and was always there, when you needed some help. I definitely want to recommend Havaa... as a matter of fact, I already have booked my upcoming stay for January 2012. This time we will try out the Penthouse.

We spent two weeks here and we were very satisfied. The appartment is excellent and its location is just perfect.

The flat I was given was severally under heated: I freeze like hell. Had to sleep with two bed duvets and my down-feather coat on. The water radiators were extremely and constantly noisy and impede sleep. The flat was not clean either: there was a fair amount of dust everywhere, hairs in the shower and stained towels. Amenities usually provided in hotel rooms (shampoo, etc). were not available. Will never go back there, not at least in the winter.