Lydia and Peter are wonderful hosts. Their communication is outstanding: proactive, detailed, helpful, friendly and informative, including letting us know of a minor cosmetic issue with the flat before we arrived (and which did not affect our stay at all). They, and their assistant Winson, responded instantly when we accidentally locked ourselves out of the flat (which was totally our fault).
The apartment is located a few minutes walk from Southern Cross station, so close to Melbourne's main transit centre. It is modern, immaculately clean, and features magnificent views of the city through the floor-to-ceiling windows (although people with a fear of heights might want to keep the blinds down).
The beds are comfortable, the bathrooms have plenty of spare toilet paper, and there are bottles of body wash, shampoo and hair conditioner in the showers. The showers are responsive (ie it takes no time for water to become hot and the temperature is easy to adjust) and water pressure is good.
One small tip for if your party splits up and members arrive back at the apartment separately: because access to the floor is tied to the key fob, the person who has the fob will need to go back down the lobby to collect others as they arrive. (Alternatively, they will need to ask someone at the front desk to grant them access to the floor that the flat is located on.)
I would recommend Peter and Lydia's place, and would definitely stay there again.