I've been playing flute for 7 years now and I've been thinking about getting a used piccolo to play for marching band and maybe concert band. I've read that the plastic-type piccolos are better so I've been looking for one of those. I found a Gemeinhardt 4P and a Yamaha YPC31, which one would be better? Thanks!

One is not better than the other. That is purply preference and opinion. I think that Yamaha piccs play great, but I don't like the scale on them. Anything like an Emerson, Yamaha, Armstrong, Jupiter or Gemeinhardt will work fine for marching.

Here is a lightly used Gemeinhardt 4P that I have that is in mint condition if you are interested. http://fluteragious.phanfare.com/4631759#imageID=97129105

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Sorry, that should read purely, not purply.

A lot of times it depends on your mouth...I am used to playing with a lip plate because of the flute, so I prefer the Yamaha YPC-32. If you are playing on a Gemeinhardt flute, the Gemeinhardt piccolo might be easier to adjust to, though. If you can, try out both instruments before you buy them - that way, you can get a better idea of how you sound on them.

the plastic piccolo (4P) will naturally have a slightly warmer sound then the Yamaha. And the Gemeinhardt piccolos are really nice for what they are. You wouldn't want to get a Gemmie for college but for high school its great and its really nice to start out on. same goes for the Yamaha. the silver may cause it to have a slightly more piercing/shriller sound. but you might get greater projection. its all personal preference. try a couple of them out and see which works best and feels the most comfortable for you