I think you should indeed try to actually pick out a feature that you believe would not feel very enjoyable to experience, at least when comparing it to the other features of working in commercial law. I do not think your example is necessarily implausible, as I have heard a number of lawyers complain about the way cross-border communication on some deals would really mess up their schedules and require them to pull all-nighters. Thus, I think you can make this point work for you, but you need to ensure you actually "sell" the idea that this would not be something you will enjoy; as you want to avoid making the impression you are just dodging the real question and make yourself look like you like everything about commercial law.