Great location for being part of the Chapel Street experience!
Susan's place is up on the top floor with great views over Chapel Street and beyond - you can even catch glimpses of the bay between the buildings. You have several tram options within a short walk and the train is less than 10 minutes away down Greville Street.
Being that close to Chapel means it can get pretty noisy, especially on Friday and Saturday nights, with a club over the road, the joys of cars doing "Chap Laps" and a pedestrianised walkway below that tends to attract groups of revellers on their way home. During the day and on other nights though it is amazingly quiet considering the location and I didn't hear anything from the neighbouring apartments during my stay.
Location highlights: try the curry place opposite the apartment building, it tastes as good as it smells; walking distance to Prahran Market, supermarkets, liquor stores and anything else you can think of. Prahran Square is a great spot to sit and soak up the sun. Prahran Aquatic Centre is a short walk and has a great outdoor pool. Take the Sandringham train down to Brighton Beach if you prefer swimming in the bay.

Highlights for me other than the location were the comfortable furniture (I want that sofa!), abundance of good quality crockery, glassware and kitchen items, large fluffy towels and the offer of additional cleaning services at the end of weeks 1 and 2 (I stayed for 3 weeks in total) to change bedding and towels. The clothes drying rack and confirmation that it was ok to use it on the balcony was a real bonus for a long stay.

Susan is a friendly and communicative host and answered any questions I had very promptly.
I would definitely recommend this place, just bring good ear plugs if you're staying on a weekend (unless you're going to be joining the Chapel Street experience). Small compromise for an otherwise excellent location and well-set up, comfortable apartment.