I so prefer metal

you can't disassemble a glass pipe, insert a medium-sized nug, and smoke past it till the nug is dripping with resiny goodness, now can you?

but if you can then let me know, I want one that can do that (since glass does actually taste better to smoke) I just love my resin-nugs too much to let go of my brass pipe! also it fits on a keychain, you simply cannot beat key-chain technology.