In reply to GForce1:
Thanks for that... I'm tempted to try a set of the Sidas half Insoles with the thin bottom half of the Salewa MFS insole system.
I'm starting to think that once the boots are fully broken in I will be able to use a normal insole, might be worth sucking it up/looking overdressed for popping to the shops and such until the uppers fully soften off and then see if a high volume insole still leads to too much pressure on my forefoot when walking.