Do NOT book early on Viking Cruises. They make it seem like booking early gives you a great deal, but they often dropped airfare and cabin prices below their early booking deals.
Example: I booked early on a Viking cruise for $1000 off cabin ($7299 went to $6299) and $999 on airfare. About a month later I received Viking brochure and the same cruise and dates had a special price of $5999 for the cabin and $499 for airfare. When I contacted Viking cruise for a refund, they said I would receive about a $1600 savings but they had to cancel the prior booking and rebook and that trip insurance would have to be purchased again for $2000. Bottom line, is don't by anything from Viking early. Wait till they drop their prices.