One thing to check when you're looking for a policy is that it covers contractual disputes. For instance, you do business with a company whose director just disappears and is uncontactable for 9 months, then suddenly out of the blue you're slapped with a law suit for alleged non payment of invoices. Despite being able to prove that those invoices have been paid it will cost you money to prove your innocence. A lot of money. Imagine just how p1ssed off you're going to be when you find that the bit in your policy that says "legal cover" doesn't cover contractual disputes...
Ask me how I know.