You don't have to worry about unwanted program that will be installed in your computer. Just follow the on-screen installation instruction of your program and any unwanted program(s) that are included in the installation file will be automatically de-selected for you
As with evrything Unchecky is not 100%
You should always use the Custom Install never default. That allows you to uncheck unwanted items.
Should you miss an unwanted item, Unchecky will most likely unselect that for you. (No such thing as always)
You are your own first line of defense. Or, your own worst enemy.......