Both truly wireless earbud products offer comparable comfort and stability features, sweat and weather resistance and battery life, but there are several key differences. First and foremost, QuietComfort Earbuds feature noise cancelling technology while Bose Sport Earbuds do not. QuietComfort Earbuds are ideal for periodic use all throughout the day, while Sport Earbuds are Engineered for Exercise. Lastly, Sport Earbuds are a little smaller and more compact than QuietComfort Earbuds.