The Mr Muscle Oven Cleaner is widely reported as highly effective at removing grease, burnt-on food, and stubborn stains, often leaving ovens looking clean or new. Many users find it easy to apply with a simple spray, leave, and wipe process, and several appreciate its quick action. However, a significant number of reviews note a strong smell or fumes, leading to recommendations for personal protective equipment like gloves and masks, and ensuring good ventilation. While generally effective, some users report it may require longer application times, reapplication, or additional scrubbing for very tough or old grime, with a minority finding it less effective in such instances. A few reviewers also highlight its versatility for cleaning other kitchen items. The product is frequently recommended and often repurchased, with some customers noting its good value.