One downside is that you may end up with a suboptimal filter. The one you linked, for instance, is P2 (~N95 in US) rather than P3 (~N100 or P100) -- so less protective against particulates. It does add some protection against organic vapors (“A1”) -- but I don’t think that would add anything in a pandemic scenario and likely reduces breathability. 3M does make some P3-rated models in that series, but I bet the cost is higher and breathability worse (because they also incorporate ratings against other gases and/or a higher rating against organic vapors).
One downside is that you may end up with a suboptimal filter. The one you linked, for instance, is P2 (~N95 in US) rather than P3 (~N100 or P100) -- so less protective against particulates. It does add some protection against organic vapors (“A1”) -- but I don’t think that would add anything in a pandemic scenario and likely reduces breathability. 3M does make some P3-rated models in that series, but I bet the cost is higher and breathability worse (because they also incorporate ratings against other gases and/or a higher rating against organic vapors).
Well spotted, thank you!