I travel once a year to Amsterdam for work, generally staying more than a week at a time. AmsterdamHome (one of the apartments available from Amsterdam Escape) was the most enjoyable place I've stayed at in six trips. It's not like a regular hotel at all, more like borrowing someone's house. Nicely renovated old (Europe old, not America old... I think it was originally built in the 1600's) house with lots of creature comforts. Very European--smallish rooms, steep stairs, lots of charm.
It's great to have a kitchen and those home comforts. Very nice staff (actually, we only saw the manager once when he let us in the house), clean, convenient to Central Station and the old side of Amsterdam. If you're insane and rent a car, parking is not so convenient. But you really don't want to do that in A'dam anyway.
Note, if you're looking for a hotel with room service and stuff like that, this isn't for you. But if you want a nice place to stay, especially if it's a work trip, this is a good choice. Includes a full kitchen with everything you need, hair dryers (I think...), TV with VCR & movies, PlayStation2 with games, some reading material, all kinds of stuff. Like I said, it's like borrowing a house.