I have my MacBook Pro set up to check for updates once a week, on Saturday morning. It's been so long since I did it I hope I'm telling it right, but if I recall correctly, all you have to do is to click "Check Now" on a Saturday morning, then make sure it's set to do it once a week. Why? Because in the rare instances when a software update breaks something else, it's not on a workday where it would disrupt things too badly. Also, I'm more likely to be home on weekends where I can get to my main Time Machine backups.