I don't know how it would be as a tone wood, but it is certainly purple, and it is extrememly hard. Think cocobolo or lignum vitae hard. They sometimes build bridges out of it.
As a neck wood insert, it adds strength and beauty. Lots of companies use thin strips of it in multi piece necks, and you can certainly consider it an upscale appointment in that regard. As an amp cabinet wood, it would be beautiful, but possibly prohibitively expensive. I'd rather a plain tolex Mark IV than a purpleheart something cheaper myself.
It's an oily wood, and holds an oil based finish very well (it will brown over time without a finish). In big blocks, it's very striking. Where it looks really awesome is inlaid in a wooden parquet floor. Anyway....
jim
