I only wear disposables, and use waterproof pants whenever possible, over the top of the support panties that hold the nappy snug. The panties absorb the condensation from inside the plastic pants, or I can wear terry-lined ones for extra safety. They provide a second line of defence against leg leaks, avoid 'damp thigh effect' where traces of moisture from inside the nappy give the impression of having leaked, and they help keep smells in when the nappy is messy. In the summer, I switch to hybrid nappies for comfort and stop wearing plastic pants; more frequent changes are needed and there is less of a feeling of protection.