You are probably better off talking to an reputable insurance broker (if there is such a thing) first in regards to liability v indemnity insurance. Of course you'll have to be wary that they just aren't trying to sell you what you don't actually need.
I have indemnity insurance but not liability for the simple reason that I do not offer advice but information, and that the client undertakes any action on that information at their sole discretion and we have a clause in our contract where the client indemnifies us against that... but like anything else, it's only words on paper until it is tested in court. Something that has yet to happen.