Fantastic location and great amenities.
A couple of things to note.
First, Rose Street is often noisy at night, even on weekdays. The flat is on the second floor above a noisy pub. The windows block out some of the sound, but if you are used to countryside quiet, or if you sleep with the window open, I'd recommend buying some cheap wax earplugs from Boots.
Second, the bed is quite small for two people, though there is, I think, a fold-out sofa bed in the living room.
All in all, highly recommended, especially if you want to explore the city by foot. Rose St is the perfect launchpad.
P.S., There's a fantastic Indian restaurant, called Dishoom, just around the corner in St Andrew Square. Best Indian food I've ever had, hands down; though be sure to book at least a day in advance.
Thanks, Charles.