I'm not paid by Sigg to say this...
I've just come back from purchasing a Sigg Aluminum water bottle. And, cautiously embraced the turning of the plastic tide. My ole 'faithful' plastic bottle is destined for the shelf where it will lie there forever. As we are painfully made aware by the powers that be, the harmful BPA's (Bisphenol A) in plastics are an harbinger to causing the infamous; 'C'. Remember the Nalgene? Like everyone else, I have used plastic containers for many years. And in some aspect, continue to do so. Although, I'm trying to curtail the use of it. I find it difficult. But, this maybe the step in the right direction.
The Sigg(Swiss made) is made from aluminum, a possible link to Alzheimers, but lined with a non-toxic water based epoxy. Think of all the aluminum soda cans out there and are they lined? Who knows?
I had another choice in the Klean Kanteen(Chinese made) water bottle made from stainless steel. There are two camps out there; stainless vs aluminum and there's a huge amount of research online. With the stainless steel bottle, without a liner, may cause water to taste 'metal like' due to bacteria buildup. A factor if you are using it regularly.
The Sigg aluminum bottle, with a liner, is reportedly taste neutral. Not for the stainless, unless you enjoy a metallic taste. And though and behold, with the Sigg bottle, alcohol can be stored but not recommended due to the obvious, fermentation = pressure danger. And of course, I don't sanction drinking alcohol with cycling!
I made a weighty decision based on the Sigg and the advantages of the liner. It basically looks like a proper cycling water bottle and that's fine by me.
My only question ... will the plastic water bottles ever be removed from pro cycling?