[ausjke]

more importantly, they're more cpu intensive and slow to deal with large files

[throwawayish]

Asymmetric encryption adds constant overhead, independent of message size.

Unless you're doing it wrong.

[ausjke]

while not an expert I disagree, encrypt a 1GB file must be different from 1MB file, no matter it is sym or asym encryption. normally Asym is for keys while symmetric encryption is for the real content.