Personally I see no benefit in this only drawbacks, the function is there for a specific purpose and when that has ended so to should your use of silent mode.
Silent/Gaming mode is automatically enabled if you are using a full screen application/game, so there should be no need to physically enable it.
I like to know what is going on in my system, that alert could be the thin end of the wedge, where notification could prompt you to take an action to prevent further infection/damage.