Viva Medi pants

Has anyone tried Viva Medi plastic pants. I wear them over my nappies. They are cheap at £7.00 for 3 pairs on ebay. They rustle a bit under my clothes but I quite like that. They are great in bed for helping keep leaks to a minimum. I get about 2 weeks out of each pair before they start to split but at that price they are cheap to replace.