New to the forum.........hello.
I have a smaller room, and I auditioned the PSB B15/Monitor Audio B1 (Bronze)/Klipsch RB15 a couple of weeks ago. I know you are asking for the larger bookshelves, but maybe my experience can be of help. The reciever pushing was a NAD.
I could only compare 2 at a time A/B. My first was the MA vs the Klipsch. The first song I listened to, Cat Stephens Wild World, I actually preferred the Klipsch. It seemed more accurate, and the acoustic guitar in Stephens' songs stood out. But, as I moved on to other music, I started to prefer the MA's, by a wide margin. They seemed much more "natural" and true; the Klipsch started becoming irritating after awhile.
Next I A/B'd the MA vs the PSB. This was a very close call at first, but again the more I listend the more I preferred the MA's. Voices on the PSB had a "nasally" ring to them. Even so, I would choose the PSB's over the Klipsch.
The best way I can describe the MA's is "natural" sounding, smooth. The PSB's a little more "grating" at the higher frequencies, and the Klipschs even worse than that. I do like the look of the PSB's, though. Those are some great looking speakers and if they would have been a little closer to the MA's in sound quality to my ears, I would have gotten them.
I did end up A/B'ing the B1 vs the B2 MA's; the B2 is the same size as the B25's you asked about. I preferred the smaller B1's over them as well. I did prefer the B2's over the PSB's, though.
I ended up purchasing the MA Bronze system with the B1's all around a 5.1 setup with the Bronze center; I have not picked it up yet because they only had 2 B1's in the box and they had to order another pair. I have an Elite 54TX I luckily ran across an open box at Tweeter a month ago at a very low price. I plan to purchase an STF-2 sub to complete the system. Hopefully, I will have it all set up within the month. Hopefully, the Elite will be complimentary to the MA's; I think it will.
So, I hope this gives some insight of PSB vs MA. Of course, you might like the PSB's more. Good luck.
Chris