se0 wrote:
you hear notice also if infected not spawned.
That is exactly the point of learning the bacteria sounds. It is not a cheat because Valve included them, labelled as such, and intended for players to learn the specific musical cues for each Special Infected so "pros" know who they will be facing in the next attack.
All this pack does is speak the names of the SI while the cues are playing as normal to help you memorise them. Even without this pack I can tell you if a boomer or charger is about to spawn.
It is no different than having a multicoloured glow around objects instead of the standard blue.
If Valve consider these a cheat they would have blocked custom sounds, glows and skins - just as they have custom models (due to them being very exploitable).
