another downside is that the WRONG kind of "car condom" can trap moisture, leading to rust/mold in all sorts of expected and novel places,

Just in case it gets worse than them eating the hood pad. A friend had his entire wiring harness is his Discovery II eaten through by a pack of "roof rats". Homeowners' Insurance paid for the whole thing. Then he hired an exterminator.

__________________
RJ
'92 500E
'75 Triumph TR 6