I haven't had that happen to me in an ID bivy, but have heard of leaking of seams in some of their bivvies! (Knock on wood). I have the all eVent bivvy and there are no seams to leak which is nice. Between this one and the MLD eVent bivvies, I really don't believe there are any better WPB bivvies available.

Nice thing about MLD is that Ron can customize a bug insert. But be aware - it does cost a bit of $$$$.