I have a "wine suitcase" (Brand - VinGardeValise) that holds 8 750ml bottles in separate compartments that has worked great flying with wine in the checked bag cargo hold. I've bottled a brew in 750ml sparkling wine bottles that take a standard beer bottle cap. The glass is very heavy but my worry is about the caps leaking at flying altitude. Anyone have experience with this? Don't want them leaking or worse, popping off. Kind of wish I'd used swing tops.