When choosing a cordless blower, the brand can be important because the blower may be part of a broader product line—most major brands design lineups of cordless tools that use the same interchangeable battery. Sticking to one brand can save you money by using more tools without buying another expensive battery.
For other types of leaf blowers, the brand is much less critical. A trustworthy brand is useful as a sign of quality, both for the quality of the tool and how easily they honor their warranty. Still, researching the blower model’s reliability is a better way to get the best quality for your money.