Studying for a master's degree in South Korea, which laboratory should I choose?

Hello. I am currently preparing for a master's program in Industrial Engineering in Korea, and I have received inquiries about lab selection from several universities. So I have a few questions. First, is there a website where I can check reviews of professors or labs? I am worried because there is a lack of information about lab life. Second, what is lab life like for master's students in Korea? Many people have shared various stories about long working hours of over 12 hours and relationships with professors or colleagues, and I am curious about the reality of it. Lastly, what should I consider when choosing a lab? I am wondering if it is better to be in a place with many PhD students or if a similar ratio of master's and PhD students is preferable, or if a smaller lab is better. I need advice. I would appreciate the opinions of those who have experience studying for a master's in Korea or useful website links.