Arcanist wrote:likely 100 with a stone axe.
Read something similar elsewhere, but can't find the post. (Search for "destroy" and "claim" got 91 pages of hits....) This would mean that they have a soak of 10.
edit: found the post(s) in the w7 announcement thread: viewtopic.php?f=6&t=31289&p=439184&hilit=claim#p438984. It's not a firm confirmation, but that is the best number until someone can confirm it is otherwise.