I quit using the bladder and tube system when I realized they add ounces to the total weight. I stick with a Gatorade liter and a smaller water bottle.
For me it wasn't the weight that made me change to bottles. I stopped using a bladder and won't start using them again until they offer some sort of 'fuel gauged". More than once I started sucking air when I thought I should still have water. When it is 110 degrees out and water still a few miles away, a person can get real thirsty.