SteveM I trial sooooo many whites every year. Skipley Swan Song was lovely. Nice growth habits and really pretty flowers. I'll keep growing it but likely would never grow more than 20 plants. Too much blush. As I've mentioned, the biggest demand for whites is with florists. "Blush" isn't as universally accepted. Is it pink blush, lavender blush, more of a pink tint (Bloomquist Tory P or Irish Ruffles) or pink/lavender center (HH Miss White)...? How you answer that will cut some orders out.
Pure white is more foolproof. Never a week I can't sell every pure white I grow. The most widely grown pure white is Blizzard. To many, it is the definition of a perfect cut flower. Long stems, strong stems, heavy producer, sturdy plant, saturated pigment (bright white), consistent bloom position, good tuber maker..." Perfect in almost every way. But, I'm still searching for something better. Maybe because Blizzard is too common? Also (in my opinion) it's a bit "chunky" with it's pointy petals and fairly thick substance. Also, it tends to have centers that have black holes (Google image search, you'll see what I mean).
As an alternative, I love Formby Alpine. It doesn't check all the boxes Blizzard does, but I think it's prettier. Round petal tips and great centers. Petals lay flat like a good formal should Long stems? - yes, strong stems? - not as good especially late season. Tuber production also quite low. I've grown it for years and never sold tubers.
I have also grown lots of Brookside Snowball. Early season, terrible stem length but it improves with 2nd and 3rd flushes. Problem is, it often also blushes depending on weather. Also can pop centers for a portion of the season. I'm cutting back on it.
Also have liked 20th Ave & Baker Road but haven't grown enough for a full comparison. Loved RJR last year but doesn't seem to make many tubers.
Anxious to try the new Ferncliff white this year (name escapes me). You name it, I've probably tried it.