For durability, stainless steel water bottles are your best bet. After testing virtually all the steel bottles we could get our hands on over the past several years, our two favourites have to be S'well and EcoVessel. For durability, quality and workmanship you can't beat these ergonomically designed, insulated bottles. EcoVessel features a handy flip straw top while the bottle-shaped S'well keeps hot drinks hot for 12 hours and cold drinks cold for 24 hours. Who wouldn't want a bottle like that?