I have heard QLN Prestige 3 (dealer in Austin) and currently own the Joseph Audio Perspective2 speakers. They are both amazing speakers in their own right. Keep in mind that Prestige 3 is a two-way floor stander, whereas JA P2 is definitely a full range speaker.
Since I heard the Prestige 3 at a dealer, feel free to take my impressions with a grain of salt. I really loved it ... it has a warmer, mid-range focused sound that I absolutely loved. The top end is somewhat subdued but not in a bad way. It is very smooth and refined sounding. And, oh, the bass on the speakers is amazing. If you have a sufficiently powerful amp you won’t need a sub despite the fact that it is a 2 way.
The Joseph Audio Perspective2, on the other hand, I feel has a more modern, clean, and balanced sound. It does not sound overly neutral (if that is a thing) or even remotely shouty by any means. Two outstanding traits: vocals (better than my Harbeth SHL5+ and M30.1), and percussion. Of all the speakers I’ve owned, I have never heard a speaker reproduce the sound of kickdrums, snares, and cymbals more realistically than the Perspective2. The soundstage and imaging is some of the best I’ve heard. They do require some breath room though (mine are almost 4.5 feet from the front wall and 2.5 feet from the side walls), otherwise bass can be a bit unruly.
To be honest, both are great speakers and I could have been happy living with either one. At this price point, you really need to audition before you buy. Good luck!