Castagnaris are held in high esteem by one row players around the world.
LA "hand-mades" are not of the same caliber. There are some players who do use them in Ireland, Quebec, England and the niche players in France who play Cajun music..those who play "other" music with one row boxes use Castagnaris more than any other maker. Simple reason, very well made and less money than "famous" LA Handmades with butt joints.
I'll wager Castagnari to LA Handmades.. 100 to one if not more.
Cajun style boxes are best for Cajun style and the Castagnaris and Beltunas (a very fine instrument) are for everything else.
I would suggest opening up the Castagnari and freeing the one reed.. that's a start.