Full-zip overtrousers avoid hopping about on one leg as the legs can be completely opened.  Indeed, with large boots or crampons on they may be the only way to get overtrousers on without having to take your boots off.

The Precip pants provide a lightweight overtrouser in Marmot's waterproof and breathable "Precip" fabric.  These are mesh lined to help wick moisture rapidly away from your legs, yet are currently offered at the same price as the unlined version.

The trousers are fully taped, with the full length toothed zips backed by windflaps.