Someone's reading my mind. I just KNEW there was bound to be a 'Favorite Whites' forum somewhere, but I couldn't find it; and here it is.
I just bought 'Lillian's Thin Ice' on the LA (from tink3472), and hope it survives and grows in my zone 4 garden. Here are a couple of pale yellow/cream sdlgs. that bloomed for the first time this year in zone 3. (I and a friend have a "test garden" at the Brainerd MN Arboretum.)
Another view of the first one