Thread bump...was looking into this myself today (with my
PandemicPedal starting in less than 2 weeks

).
Our house insurance is currently with Sheila's Wheels (

)....I just chatted online to add my Specialised (value just over a grand with panniers/bags). After some checks, they told me "your total additional premium is £0. This includes you administration fee of £20.00. However, the change today has reduced the premium so the two amounts have cancelled each other out."
Seemed a decent result to me!
Now I know when the bike is not in a garage or locked to an immovable object, it isn't covered (& I will be doing a few nights camping along the way, so will need to be careful there!), but even so, that seemed reasonable enough.
I had done a check on 'cycleplan', which started at just over £50 without any of the extras they list.....