Take a swig of water out of your CamelBak Womens Charm Hydration Pack to calm your thirst when you hike down Angels Landing in Zion or mountain bike in Moab.
A water bottle cage works OK on the bike leg of your triathlon training session, but it doesnt do much good when you get to the run. Use the CamelBak Fairfax Hydration Pack for both.
You are not a camel and you dont want to wear a backpack while you train for the marathon. The CamelBak Montara Hydration Lumbar Pack solves your need-water crisis and your nothing-on-the-back-please preference.