We booked the hotel through a European hotel service (www.hrs.de), which we've had pretty good luck with in the past. It rated the Best Western Museum Hotel as a 4-star hotel, but I would dispute that based on our accommodations.
The hotel is located on a beautiful canal in central Delft, very close to the Oude Kerk. We were given room number 1 (a word of advice - avoid rooms 1 through 4). This was on the ground level in the back of the hotel, so no canal view. We actually had a partial view of a fenced dumpster. It wasn't really offensive (it didn't smell), but it wasn't what we wanted to look out on either. Otherwise the hotel was fine. Our room was small but adequate with a very small television and double bed. The bathroom was relatively nice with a full bathtub/shower and hairdryer.
Breakfast was included in our rate (75 Euros per night), which was a decent buffet with very pleasant wait staff. Everyone spoke English, so we didn't even have to try and speak our broken Dutch to them. A decent place, but you could likely do better at one of the smaller 3-star hotels.