I saw the church during the day and went back for the concert. Considering the church was undergoing repair work with dirt everywhere (as per previous review), the panoramic experience was non-existent. Considering so many other beautiful churches in Vienna (St. Peter's for one, which only ask you for donation for their mid-day organ concert) you're not missing much out by skipping this until the work is done.
Concert was a complete tourist trap with "orchestra" consisting of only 4 people. Vivaldi's Four Seasons was played in a random order (We moved from winter to summer then to fall and spring, with select movements only) and if there are only 4 people playing with one soloist, this is not an orchestra, but a quartet with a soloist. (There are so many beautiful chamber music pieces that I would've happily listened to, but you cannot do justice to Beethoven's Symphony number 5 with 4 people!)
As with any other church, acoustics does not work very well for faster movements (as echoes in the church tends to mumble the sounds) and with 30 euros per person (cheapest tickets here), the musicians were mediocre at best (you can catch Wiener Philaharmonic at the Staatsoper for the price if you plan ahead).
Also, there are no bathrooms accessible at the church and we were directed to university around the corner to use their facilities.
If you're planning on visiting the church, do yourself a favor and skip the concert. It's overpriced and not worth your time.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.