I struggled to get a good multibike policy when I got the Falco. Best option was with Bikesure which is part of the Adrian Flux mob. They are 2 different policies but they set up an online area where all policies available and changes can be made etc. which make it like a multibike policy. I ended up getting a significant discount buy taking a second policy so was by far the cheapest option. I can ride other bikes not mine fully comp too, although there are limits to the total claim value.
I used to use this lot. Found they were reasonably priced (out at Banchory anyway).
Never made a claim though, so I can't comment on their performance....