I'm always interested in attempts to improve on the basic design of the whistle. And Nick Metcalf has just brought out the interesting Overton-based Skellig Low D (
https://www.youtube.com/watch?v=lndWFXLWyfA) a prototype of which has been around for a while now. It basically has two "improvements." First is a head that is made differently from the Overton/Goldie. According to Metcalf, it is one piece apart from the top of the windway and this has allowed him to coat the two windway surfaces with Teflon to cut down on clogging. If the video is anything to go by the results are amazing. However, the design would appear to restrict him to one windway height. The pictures suggest it is what Colin Goldie would call a soft or very soft blower and that's fine if that is what you want. I would a narrower windway.
The second innovation I find far more interesting. It appears that, without affecting the bore, he has shaved down the thickness of the tubing starting at the first hole and gradually increased the thickness again down the whistle. He suggests that this helps to better balance the volume of the high and low notes, making the high notes softer and, though he doesn't mention it, probably easier to reach. This isn't a new idea. The tapered Lochlan held to this same idea but it's nice to see it, at last, in a production aluminium Low D.
Living in the UK makes it too expensive for me to buy what with shipping and import duties. Besides which I wouldn't want a soft blower nor a Low D that didn't have the rounded holes I love on the Goldie Low Ds but I would be curious to see someone review one . . . and confirm or not whether it does what Metcalf suggests it does. Maybe he would be interested in a whistle tour for it in the USA.