You and your hiking mates will regret it if you don't. Seek out a reputable store and an experienced salesperson to find the best fit. Unless you're replacing a specific size and model, exercise extreme care with mail order purchases or discount-mall shopping. There are too many variations in the human foot and body to take chances. Someone who's flat-footed and 240 pounds won't be comfortable in the same boot as someone who has a high arch and weighs 145, even though both may have size 10 feet.
Boots are one of the few items that are hard to rent.
Plunge wisely, watch for sales, and see if the salesperson will bargain.