Reviving this thread as a prospective concertina player.

I'm wondering what people would recommend for someone who'd be interested in playing contra dance tunes at some point in the future, as well as the occasional sea song. I've found a few critiques of anglos to the effect that modern dance tunes tend to be keyed to D, which can be a bit of a problem for an instrument tuned to C/G. I'm curious how much of a difficulty that really is, and whether an english or duet would be better suited to the sort of music I'm interested in.

Thanks