I like the for multiple reasons. 1) I cherry pick workouts so if I'm not going to my box then I use these to come up with a workout so I don't pick only my strengths and never work on weaknesses. 2) it's hard to be creative for every single workout you build for yourself.
The only con is that there are limited movements. But obviously these dice aren't the law of god. If you want to do burpee box step overs but you rolled KB swings, then just do the box stepovers.