[edit]Plastic bottles are fine and more brands available every year.  Pack 'em out!
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I'm an old school guy, when you say bottle, I think glass.
I've never had beer out of a plastic bottle :-?, or even a clear glass one ;D so I'll take your word that you can get decent beer in them.
Main reason I brought it up is that I didn't want any Newbie to think glass bottles or cans were okay to bring in.
By all means, if your willing to lug it in and pack it out, go for it.