For me, if it's a kit I've had before or I have multiples of, I leave it alone till I'm ready to build it. I have a case of the reissued Ca Hauler Pete and a case of Italeri 378s. Why open every one of them. If it's a kit that's new to me, I open it right away. Just to check it out, look over the chrome, give the instructions a quick gander, look it over for the mods I have in mind, and how am I gonna go about doing the mods.