I've owned both Buice and Permar trumpets, and both are top quality. Buice for interchangeable mouthpieces is the only plus.
But to throw a curve ball for additional consideration...for a straight up "field grade" hunting yelper its hard to beat either Mark Sharpe, or Tony Ezolt, river cane or wing bone. Over the years, my EZ wing bone and my Sharpe river cane have seen more woods time than all the big name trumpet makers I've owned, Hegler included, combined.
It's funny you mentioned this because I never called Mr. Billy yet, because I've been researching Mark Sharpe cane yelpers and wingbones.
Lots of choices!
Thanks to everybody for all the suggestions.