The best part about this place is that the hosts are pretty communicative throughout the process and sent over very detailed and helpful information about how to get to the apartment and a thorough guide on places to eat/see in the nearby vicinity. The apartment was clean with all necessary amenities including some nice touches like a bottle of wine and some candies. The location is also great for getting into the center -- you can walk to the Opera House in ~10 mins or ~5 mins to Karlsplatz and get the metro from there to anywhere. There are also scooters all over to the place that can have you to Stephansplatz in under 10 mins. It's also a few steps to the Naschmarkt as mentioned which is both fun and convenient.
The immediate location, on a pretty major road, can be a bit noisy due to the traffic outside. There is also a club across the street that has very noisy patrons on weekend nights, which is bad enough, but it's especially obnoxious when they are leaving on weekend mornings. We were woken up both Saturday and Sunday at ~6-7am by loud groups standing outside the club for 20-30 minutes while leaving. Nothing the hosts can do about this but something to note. The windows provide some good sound protection but the apartment tends to get hot and stuffy in the summer so you really have to pick your poison there.
Some of the photos on the listing are a bit out of date, a couple of the nice pieces of furniture (eg the coffee table and nice wooden stand in the bathroom) are not there. Also a couple of key items were broken when we moved in. One of them was replaced fairly quickly by the hosts but it's still just a little annoying to have multiple things not working, one of which was a fan which is indispensable on the hot summer days.
The pocket wi-fi is an amazing perk in that you can take it with you, but it does seem to be a bit flaky. It goes in and out, dropping a few of our voice calls, and we had to have the hosts reset it once when it stopped working.
Finally I will say that imo this place is good, not great. It's a decent value for the price and I'd stay here again but wouldn't seek it out. I have to mention that I think the rating is a little artificially inflated because the hosts are very insistent about asking for you to give them a 5-star review at various points during the stay and a bunch of people probably felt some pressure to do so, which I did as well.