The biggest problem with any Low D apart from the stretch , is volume
Not bad for Solo stuff , or with one singer , but in a group , hardly audible without a decent Microphone and P A .

But the same could be said of many flutes, concertinas, bouzoukis, mandolins, singers ... I've played with three and four piece acoustic bands and got myself across perfectly happily. Doesn't work up against a horn section or a rock 'n' roll band, but unless you're equating volume and quality, or volume and 'validity', I'm not sure where that gets us. I wouldn't play low whistle for the Morris side, but that's a particular case and I see a lot of people playing various instruments for Morris sides who can't be heard on the other side of the set.

Oh, and the answer to the original 2007 question is Overton / Goldies :)