Paradigm 3f, KEF reference 3, Monitor Audio PL300II

I've been auditioning speakers in the $15,000 range and am almost ready to decide.  My short list right now is the KEF Reference 3 and the Monitor Audio PL300II.  I'm planning to hear the Paradigm Persona 3f this weekend.  I've also heard speakers from B and W, Wilson, Wilson Benesch and Proac but none made the final cut.  I really expected to be blown away by the Proacs and, while they were very good, I prefer the KEF and Monitor Audio. Unless the Paradigm is even better, it will be a tough call. They both seem to have great imaging and soundstage, reasonable bass and pretty life like presentations.  We all know how hard it is to compare and contrast speakers, especially when there's a large time gap between listening sessions. The Monitor Audio dealer has offered to bring them to my house, set them up and let me live with them for a week at no cost. Sounds like a great offer but I don't want to accept if I'm leaning more towards the KEFs.  Any helpful advice would be appreciated.  
For that price, if you go with KEF, I'd go for a set of used Blades over the Ref 3.
The PL300 II’s are a very well rounded speaker that is great for long listening sessions. I’m very impressed with all of the Platinum II series for the price. For 15k you could get some amazing used speakers. There is really no need to limit yourself to such cookie cutter products.
I have been trying to talk myself OUT of getting a KEF Reference 3 for the office because I definitely will be getting a Blade 2 for my family room. I was thinking it maybe too much of a good thing to have 2 similar types of speakers.

I have looked at exactly the 3 speakers you have listed. I have not heard the Monitor Audio but have read reviews, mostly good. However, the footprint of the Monitor Audio speaker is a little large for my office.I heard the bigger Persona 5F in a terrible room but I liked the speaker because it disappears well. So far I have not been able to convince myself to deviate from the KEF 3 for the office. I love the sound of the new KEF speakers. 

However, recently the light bulb in the brain has made me consider shifting gears for the office and try something out of left field such as a German Physiks Unlimited speaker or some brand using different tech than a dynamic speaker. 

Not sure my ramble here helps you but you will have a good speaker whatever you choose from your list.