I have used Camelbaks for forever until I learned about Hydrapaks on my trip to Florida in January. I like the Hydrapak SO much better! The closure system makes it so easy to clean and dry out (you can turn the bladder completely inside out after washing to dry), and the drinking tube is a bit larger for better flow of water. They make a variety of sizes. I have a women's specific one which essentially is just a bit shorter and the chest strap is in a slightly different, more ergonomic place.