Pros: great location, 5 min to the Opera, 20 min to the Cathedral, 20 min to the Belvedere. Many cafes and restaurants around. Metro very close.
Great host, very friendly and helpful.
Great apartment, sunny, clean and spacious.
Great internet connection, mobile device that you can take with you wherever you are.
Air condition, washing machine and coffee maker very useful!
Cons: there was not shampoo, nor shower gel.
I didn't mind the IKEA furniture, but the IKEA mattress felt "cheap" and uncomfortable.
Quite loud during the night.
Stores in the bedroom were stuck and at 5 in the morning it was too sunny to sleep.
Overall, I would highly recommend this apartment to anyone visiting Vienna.