I ordered the HydraTube in blue and didn't like the color. It was also larger than I would like. I could not find listed dimensions but convinced myself this was smaller. They are the same size. That said, the clear looks smaller and the bubbler looks narrower.
The AquaTube has an easier draw with the cap removed. I prefer it this way. It's also easier to clean and fill with a removable cap. The cap can be inserted for travel, it will help reduce spilling but it will leak if it is laid horizontally.