Whether the vent is bad for others depends on whether the air from your breathing goes through any filter. COVID spreads with aerosols, and the more aerosols in

Whether the vent is bad for others depends on whether the air from your breathing goes through any filter. COVID spreads with aerosols, and the more aerosols in the environment, the higher the chance of infection. You actually need to breathe in quite a bit of viral stuff in order to get infected. If the vent allows for more aerosols than a closed surgical mask, then the vent is worse for the people around you. It's not really relevant where the vent is in the mask. But whether the difference is significant enough to cause a problem, I don't know.