CLINICAL RELEVANCE: Headset-based simulator training is increasingly utilised in eye care education, offering opportunities to improve clinical skills in a controlled, reproducible environment. These tools support the development of innovative training approaches in eye care. BACKGROUND: While the educational advantages of headset-based simulators are recognised, the potential challenges and limitations that users may encounter remain understudied. This study investigated changes in user comfort and vision functionality following a 40-minute headset-based simulator training of indirect ophthalmoscopy. METHODS: Fifty-four participants aged 20 to 45 years (21 eye care professionals and 33 optometry students, analysed as a single group) underwent a 40-minute training session using the Eyesi binocular indirect ophthalmoscope simulator. User comfort with a custom-designed symptom questionnaire and visual functions using the RAF ruler, von Graefe technique, and prism bars were assessed before and immediately after the headset-based simulator training session. RESULTS: Following the headset-based simulator training, there was a significant recession of both the near point of convergence ( CONCLUSION: Forty-minute headset-based simulator training can lead to altered vision functionality and pronounced discomfort in some individuals, highlighting the variability in individual responses to training indirect ophthalmoscopy skills in video see-through augmented reality.