I am the OP. With regard to the KEF Reference 5 speakers, after about 1 1/2 years, I’m really liking them. I think they do require a long break in time. The imaging, soundstage and bass “slam” are impressive. Also, I substituted a new Krell Duo 175xd Amplifier for my old Audio Research tube amp resulting in much more powerful bass. And this week, I added Isoacoustics Gaia 1 footers, which make an amazing improvement...more than I ever would have believed. The sound I’m now getting is pretty unbelievable.
As for the Paradigm Persona 5 comparison, I listened to them before deciding on the KEFs. I liked them and considered buying them but obviously chose the KEFs. I did not have the opportunity to hear the Paradigm and KEF speakers side by side or even within a short time frame. It’s obviously a matter of personal preference. Dave Lalin (the Audio Doctor) has a great ear and provided excellent advice. I give a lot of weight to his opinions (even though we may have a small difference regarding the Paradigm vs. KEF). At his recommendation, I’ve bought the Innuous Zenith 3, the Krell amplifier and Wireworld interconnects. I did not have an opportunity to hear any of them before buying and relied on his advice. Perhaps not the ideal way to buy equipment but I have not been disappointed.