This is not a "must see" film. It is also not a "piece of crap". Obviously, this film is somewhat polarizing to produce the disparate reviews it has received here. And just as obviously, some of the people who watched this film have an anti-gay bias that makes one wonder "why the hell were they watching this film?"
There are aspects of the film that I liked. And many I did not. I do not want to be too dismissive of "A Perfect Ending" because I feel the writer/director invested a lot of care in this film and tried to produce a beautiful product.
Many of the things I found off-putting were intentional. For example, the editing that was sometimes choppy. The music that, in places, was designed to create an air of the mysterious and sacred. These are artistic choices that sometimes did not work for me. Often, they took me outside the film, especially since the pace was slow. The pace itself could have been brisker in parts.
Also, Jessica Clark (who plays the escort Paris) spoke with such a slow, deliberate pace it was distracting. It reminds me of Nichole Kidman in "Eyes Wide Shut", but Ms. Kidman's character was under the influence when she spoke that way.
Lastly, I found the sexual politics of the film annoying. Often they are inserted where it does not serve the story.
All in all, this is an average film by a filmmaker who could probably produce a much better product.