Go with Bruder.  Plastic and very tough and I believe they have a lifetime warranty as well.  Lots of cool stuff, too.  Company originates in Germany, so there are lots of different European type machines.  Price is right too.  One of the biggest pluses is opening the package and the toy comes out.  No wires, screws, padlocks or other impossible gadgets to get off before the kid can play...  Ben