Hi, If it's plastic they will chew it
and I'm not real familiar with the material used in this plastic either, if it could in anyway be harmful to your new bunny.
Usually the galvanized metal is used for caging or if you make it, wood and turkey wire (the small square holed wire) yes, they chew the wood also. 
I have had both in my lifetime of keeping bunnies, the ole standard bunny hutches with wooden house and wire front run, and large long galvanized metal cages. (easier to clean)
Here is a link to Martins cages for Rabbits, very NICE , all sizes and pricing. I have a squirrel cage from them.
Rabbit Cages/ Martins
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PHEve/ Eve
Contact PHEve