A Yamaha 30 is a metal piccolo with a cylindrical bore.
The U.S. Navy Band uses the resin-body, metal head YPC-32 for outdoor concerts, anytime cracking of a wood piccolo would be a problem. Set up properly, these are a REALLY good picc for the money. (The Navy Band has recently ordered Brannen-Cooper rose-gold headjoints for the flutists, so you can be sure that they would never play an inferior instrument!) Anyway, the resin, conical-bore YPC-32 has some of the best intonation out there for a piccolo, the 'Pro" YPC-62 has the same design, but in wood. I have played my 62 with a 32 for duets, it works very well because of the consistency of the intonation with this design.
Gemeinhardt metal piccolos are tuned sharp. (Any Gem. metal piccolo that I have ever seen has a conical bore.) IMHO, that's why 'a metal piccolo sounds screechy.' Gemeinhardt instruments are ubiquitous here in the U.S. I have also had the pleasure of hearing a silver Haynes piccolo, they sound absolutely lovely. The difference in the piccolos is in the design, and the quality and consistency of the setup/padding.
Our orchestra principal has an old model wood Gemeinhardt. Nice picc. This model (the 4W) and the Yamaha YPC-62 should be available used for around $1000. If you buy one off eBay, add about $250 US to get it padded properly.
Try Nancy Shinn of
www.flutestar.com as she often sells rebuilt piccolos and will help you find a good model. She is an outstanding technician.
Have your fiancee' take the school piccolo to a qualified technician. Have her tell her instructor that the horn has problems and needs to be looked at. The school SHOULD pay for repairs. You may find that the thing is cracked, and essentially unplayable. Or you may find that with proper repair, it IS a nice piccolo. Any piccolo should have a clean, oil and adjust yearly-this one may have seen a repair tech last 15 years ago...
BTW, a Yamaha 32, or even 62, is essentially designed for ease of playing, rather than the ability to get a lot of finesse and tone color out of the piccolo. The YPC-62 is immensely popular for its ease of playing and intonation. When I picked up a Zentner, it was much more difficult to keep the intonation centered where I wanted it, versus the Yamaha. However, it offered a lovely depth of sound that made the Yamaha 'thin' by comparison. Most doublers would be well advised to keep their Yamaha 32 or 62. However, 'serious' piccolophiles generally will start trying out pro horns by Hammig, Burkart, Zentner, Keefe, Haynes, etc. and then want that sweet, deep sound. Many will be offset by the hard work that it takes to learn to play these instruments well, and stick with their Yam or Gemmy 4W which are easier to play. The Yamaha YPC-82 is nowYamaha's 'top' pro horn; it is a model 62 with sterling keywork, and an additional headjoint in sterling silver.
Good luck!
Tibbie