This is a topic of some debate.

Some people don't want to risk using anything other than glass or stainless steel, so they are naturally concerned about this.

Some people don't mind storing filtered water in some form of beverage safe plastic.

What's the best option?
depends on how paranoid you are and how much you think you are risking your health by drinking from some food safe plastic container.

Glass is most inert, and best.

Stainless Steel is also inert, but it's metal (and there are different stainless steel alloys, but should not cause any problems with acidic foods).

Adobe/ceramic is also an option for a water storage container in the home or office, but I'm not sure if ceramic sealants leach into the beverage.

Plastic is last and you know from the greeniacs guide that there are a variety of plastics one can select from. All plastics leach over time, but some leach less than others, and the studies claiming endocrine disruption are hotly debated.

What's your opinion?

I believe that either glass or stainless steel are the best options.

Stainless Steel is the material most often used in the food processing, dairy, and brewery industries. It's easy to clean, durable, inert, sanitary, toxin-free, and non-leaching.

Both glass and stainless steel are good alternatives to plastics-as plastics account for an obscene amount of waste in our landfills and oceans.

Although if plastic is your only option, avoid keeping your filled bottles in high temperatures.