Many reviewers praise the headphones for their excellent noise cancellation, comfort, and sound quality, especially when purchased on sale. Some reviewers highlight the headphones' lightweight design, long battery life, and intuitive controls. However, a few reviewers express concerns about the headphones' build quality, battery life, and occasional connectivity issues. Overall, the reviews indicate that the Bose QuietComfort 45 are generally well-received and considered a good value for the price, especially when purchased on sale.