Positive: Compared to other brands, this model has large breathing holes for lots of airflow. Negative: The rubber smells awful. I thought the smell would fade overtime, but it has been a couple of weeks, and still has a strong odour like burnt tires/poor quality rubber. The rubber part at the bottom of the mask smells so bad, I don't even want my pony wearing the muzzle, instead he wears another one from the local store. The rubber on the Roma muzzle is also very soft, and I would think the little guy would wear through it very quickly. I would not buy this product again.