There is a lot of hysterics about plastic water bottles copied around the web. Much of it is published by web sellers of competing products. As far as calling Nalgene bottles unsafe (those labeled with #7 on the molded bottom) due to the theoretical leaching properties of polycarbonate (phthalates), I suspect the risk is extremely low, probably nil (now no b**ch t*t jokes, please!). There certainly seems to be no sound evidence of leaching in typical use with consumable beverages. Most bottles get flushed, cleaned and stored dry (or at least drying), the leaching between filling to drinking is minimal. LDPE, (polyethylene, #4) seems to escape criticism. That is the material most cheap shop promo water bottles are molded from anyway.

As far as alternatives go, the Sigg and Sigg-copies are aluminum alloy with some kind of resin liner that is supposedly food safe. (Strangely, they are no longer considered fuel safe due to temperature-induced expansion of hydrocarbon stove fuels when filled and subsequent ruptures and leakage). I guess I am betraying my age, but I remember Sigg was the fuel bottle for backpacking, about the time the Svea 123 was the stove to use. Oh well. They look cool, anyway.

My only gripe about the Sigg is that they are thin-walled and dent easily and that bubble-topped twist-open spout is low-flow compared to squeezing a drink from a LDPE bottle. The steel bottles, like the Kleen Canteen have a retro cool look, but like other single-wall metal bottles, they don't insulate as well as the cheap plastic bottles, you can't squeeze them and they are heavier, if weight shaving is an issue. One nice thing is that they are wide-mouthed, so you can drink easily from them, like with a glass.

I have bought them all and I have come to the conclusion the plastic bottles, while not the best looking, are still the most practical. It doesn't hurt that they are a lot cheaper, either.