After doing research for a number of days, my wife and I spoke with Colin Goldie today and ultimately felt comfortable purchasing two of his Suprano D tin whistles and one of his Tenor D low whistles (all at the standard soft). This information was helpful and saved Colin time in his explanations regarding the term standard soft. Thank you.
You’re in for a treat! Colin’s soft-blowing high D whistles are, in my opinion, the best high D whistles that anyone has ever made. Nothing even comes that close, if you ask me (at least, of the 50-or-so whistle brands I’ve tried).
Just remember to be patient while you’re learning to play these instruments. They’re not nearly as easy to play as a lot of other whistle brands. They take very precise breath control to play well, and they can be a bit unforgiving for that reason. They also tend to clog easily, so I recommend washing them with soap every time you’re done practicing to minimize this. But ultimately, they’re worth it! The sound you can get out of them is unparalleled.