what sort of duet? - Crane is fairly straightforward. McCann is supposed to be pretty easy too, although i've not played one. Haydens are bloody stupid.The issue is more whether you have to play in F to accomodate northumbrian pipes!
Certainly if the tune is in D, then it's harder on the N pipes than on any concertina, but if it's in F, Bb etc then the pipes are going to be easier. no?
EJ