We really liked Lela's apartment! It's conveniently located next to a subway station from which you can directly get both to the city center and CAT train station (fast train to the airport). There's also a very good restaurant nearby called Das Eduard which is worth a visit regardless of where you stay in Vienna — yes, it's that good.
The apartment itself is stylish, clean and comfortable, and there's a nice bean-to-cup espresso machine in the kitchen.