I'd rather sleep on a park bench.
Please understand... the Adelaide is a hostel, the Dakota is a "hotel" managed by the same owners. The Dakota's rooms are a small upgrade from sleeping on the street in a sleeping bag.
I stayed there in 2007 as a college student, and the experience was adequate for one in that stage of life looking for a cheap place to spend a night in the heart of an expensive city. So I blame myself when, five years later, I planned a week long getaway for my husband and myself and booked two nights in a private room here expecting the same budget experience. We quickly realized that we no longer prefer this setting and are unable to relax in dirty, noisy "hotels." 
Like everyone before me has stated, understand that if you book a private room through Adelaide Hostel, you are not really staying at the Adelaide hostel. You have to check in at the Adelaide, but you walk a block north to the Dakota Hotel with your bags. The Dakota has a smidgeon of appeal if you like ancient hotels that "preserve" antiquated details, such as the lift in the lobby which only sometimes works and is more than a little scary.
Despite having much to say, I will keep this short, as others before me have described basically down to the last detail my very own experience. The street noise is terrible, the front rooms are directly above a bar, there is no air conditioning, the bed sheets and covers are full of holes and stains, the pillows lumpy, the mattresses worn out. Our ceiling fan was broken so we had to sleep with windows open, which only made the traffic noise even worse. The staff was average, but this isn't a four or five star hotel, so why expect anything better? The cleanliness of the room was... severely lacking. I never took my shoes off for fear of touching the carpet with my bare feet. I'm shocked we didn't end up with bed bugs or something worse. The location, while close to many downtown sites, is dirty and feels unsafe. My husband was approached by a male prostitute on a trip to the drugstore.
For us as a couple, it was $40 per person ($80 per night + taxes), and is $55 per person on weekends. We cancelled our second night's stay, requested a refund (pending), and moved to another hotel where we paid quite a bit more, but had a real night's sleep in clean and well-furnished room. 
My advice is that unless you are a student or a single person desiring a HOSTEL experience, or unable to afford ANYTHING better, do not book a private room here. You will not find it relaxing or enjoyable. Spend $20-$40 more and stay somewhere nicer.