My husband and I stayed here for 1 night and had a great 24 hours in the city. The hotel has a very classy and luxurious feel, lighting is moody, and staff are very friendly and attentive (as you'd expect of a hotel of this quality). It is located in the Paris End of Collins St, being a fantastic spot for exploring the shops, bars and restaurants in the city (the Spice Market is underneath the hotel, and Flinders Lane restaurants are just out the back (eg. Coda, Ezard)). We had breakfast the next morning at a laneway eatery on Degraves St, which is only a short walk/one stop tram ride from the hotel.
We stayed in a King View Room on the 22nd floor, and the view was excellent - all across the south side of the city, including the Yarra River, MCG, Botanic Gardens & Governor's Residence, Shrine of Remembrance, Eureka & Crown towers, and we could see as far as Albert Park and the water in Port Philip Bay (St Kilda).
The room was a little smaller than we had expected, but had a very comfortable king bed. We didn't get a great night's sleep as the room was not totally soundproofed - we could hear next door both sides (one rattling coathangers in the wardrobe, the other's water pipes when taking a shower). The room was also too warm without the air con running, which meant a noisy and disturbed night's sleep with the air con unit on. I would take ear plugs next time! There was also a charge to use wi-fi in our room, which we thought was a little harsh given the price of the room. There was an ipod docking station within the base of the digital alarm clock. The bath was one of the biggest I have used, a good full person size - I could lie back and totally stretch out my legs (I'm 5'6").
Given the price of the rooms and the fact that we were leisure travellers not business, we were a little disappointed with the leisure facilities - the hotel does have a steam room, sauna, pool, spa and 17 degree plunge pool (for the brave!) however the facilities seemed to cater more for the business traveller than leisure traveller. The pool area felt a bit soulless and functional - there were no loungers around the pool to relax, read a book, have a snooze etc. - you were just there to use the facilities then head back to your room. My husband and I could not take a sauna or steam together as these are not communal but rather there are single-sex facilities in each of the changing rooms. We didn't use the gym facilities, but they looked fairly well equipped.
The food in the hotel restaurant (we only had lunch there), Collins Kitchen, was excellent, if a little pricey - a lunch of 2 sandwiches, 1 bowl of fries and 2 glasses of wine came to $90. The concept of the Collins Kitchen itself is a great one though (different culinary themed open kitchens with chefs cooking fresh produce while you watch), and it is certainly worth a wander round the various cooking stations even if you don't take a table.
Overall, whilst we had a very enjoyable stay, we didn't feel that it was great value overall for the leisure traveller in light of the things it lacked in the leisure facilities and no free wi-fi.