Pros:
Location: A great place to stay. The flat is big especially for HK standards and even more in that area. Area is great if you want to be central in HK. Great for tourists and business trips. 5 mins away from MTR (Wan Chai) and even closer to buses (if that is what you'll take). Despite being so central, a quiet place as you are off the main roads. Finally just across one of the best Thai restaurant in HK (you'll see the queue there everyday but you can get take out in 5 mins!).
Flat: I believe it's been recently refurbished as I would say it's up to service apartment standards. Place is really big so you can stay long term and don't feel claustrophobic. Bed is big enough and good mattress. You have a small balcony for your morning coffee. You get all you need for daily living (i.e. iron, small iron table, cutlery, towels, coffee/tea pot, cooking place (wide open kitchen), fridge, internet, wardrobe space, etc.). There is a TV, but see the cons.
The owner (J): Responsive and helpful.
Cons:
Location: Not really a cons but be aware that most taxi do not know that road. I suggest you tell them to go opposite Wan Chai Market and drop you at the bus stop. If you arrive late (to be confirmed by J what time is late), you would need to pay a small fee to get the keys as they don't live around and would need to take a cab to deliver them to you. It should be mentioned on the ad.
Flat: As mentioned, the balcony is smaller than i expected and "shared" with the never (there is a partition). To note that in 2 weeks, I've never seen the never on the balcony. The TV didn't work when i arrived. It was supposed to be repaired the next day and the repair man came but not only I couldn't make it to work still, he forgot to close the balcony door (some miscommunication with J at that point). I don't really watch TV, so i didn't care.
Overall: I give this flat and J a 4.5* rating. This would get a 5* rating without the small inconveniences mentioned above.
But very good stay, so thanks J.
Matthias