Do I need Julbo glasses for the climb? I have a very good pair of Costa's that have excellent coverage. Just trying to get down the nitty gritty of what I need to buy and what I should rent.
If your sunglasses block 100% of UV, have overall light transmission <10% or so, and are either wraparound design or have side shields so that reflected light from the sides or underneath is blocked, then they will probably work fine. If not, or you're not sure, then glacier glasses aren't that expensive.