Only worn them once but comfortable straight away. I always wear jelly heels as standard so have not had any comfort issues in heel area with them being low to the ground. Snug fit and super light. Great on both Clay and Artificial Grass. I had so quality issues with previous 4.1 Ubersonics as mesh material split on both shoes which makes them look a little scruffy but still a great shoe and sole as good as new and I've had them nearly 2 years and have played 102 doubles and single matches in that time. . If the mesh on top of the shoe has longer life span then I will be more than happy as they look great as well as feel great