I actually have zero knowledge, my 325 insight was gleaned from others in previous posts being adamant that's what it was. I recall someone saying they had both the 325 Coniston and this boot and were convinced it was the same. Maybe I should mark it as hearsay...
I specifically wanted something not sleek; a real country boot just not quite as bulbous as the stock Islay. I could have lived with it - I mean, if it's good enough for Bond, right? - but it was just a bit too much for me. Just a tad.... these seem perfect!
In that case I have much higher hopes for my replacements - similarly being sized down 1.5, like you. Can't wait!
Good luck on the replacements. Let us know how the sizing works out for you.