The good and the bad about 'Moonstone' (Carruth, 1998). First the good:
And more good:
This is a vigorous and strong grower to well over 6' (2 m) if you allow it, and this is true both grafted and own-root. Also wide-growing, again 6', because as it gets taller and taller the stems drift sideways from the weight of the flowers. The flowers last well in a vase. They nearly always grow one-to-a-stem, and the stems are long, straight and fairly strong. Production is excellent in warm weather, when daytime highs range from the mid-60s F to the high 80s F (18 C to 30 C). Rebloom is not abnormally quick, but quantity of bloom is good, several dozen per flush.
Now to the bad...which may seem to overwhelm the good points, but many of these are nit-picky. The most significant "bad" is not nit-picky: this cultivar is highly vulnerability to Rust, and by December with even a modest amount of rain all of the foliage is the color and texture of a handful of Cheetos.
Botrytis is also a problem if there's rain: red spotting on the white petals is common before May and after October. Since the flowers have a good number of petals (40+) with thick substance, brown soggy centers are also a problem in damp weather. I've found that one well-timed spray of a first-rate fungicide like Banner-Maxx in spring, after the plant is fully leafed out but right before it starts to rust, and one more application of fungicide at the beginning of September, when the nights begin to cool down to below 60F, eliminates 90% of the rust until after Christmas, when it's almost time to prune anyway.
It tends to have a poor fall, but mine may be just plain tuckered out from from a long summer's labor. Though it is more productive in warmer weather, during very hot spells (90 F+, 32 C+) the petal edges will crisp and brown, while the rest of the flower survives.
Moonstone in full sun, crispy-edged when temperatures are in the 90's:
If you insist, as rose exhibitors do, on symmetrical perfection, 'Moonstone' can be iffy, because split centers are common. A "split center" is an asymmetrical fold in the center petals of a rose--if you don't know what the term means, you probably don't care--it's an exhibitor thing...though...I admit it bugs me a little bit.
Moonstone with a "split center":
Sunken centers (when the very innermost petals are shorter than the petals immediately surrounding them) are not as much of an issue. Again, that's an exhibitor's concern, not a concern of common mortals.
No, it's NOT pretty, it has a "sunken center"!
There's one other problem--fragrance. At best, it's mild; most of the time it's non-existent. A rose so lovely needs some fragrance, but the color combination of porcelain white petals edged in pink seems to spawn scentless or near-scentless roses. Other Hybrid Teas of this color class, like 'Mavrik' and 'Louise Estes' also lack alluring fragrance but will give consistently better form (even more beautiful, yes!). You'll need to buy those from retailers who specialize in Exhibition varieties. 'Louise' rusts almost as badly as 'Moonstone' here. 'Kordes Perfecta' has a good fragrance, but can be stingy with blooms.
I've gone on and on about the drawbacks of this rose, but if it was so awful, I would have gotten rid of it a long time ago. Keep in mind it has excellent productivity, likes warm, if not hot weather, and forms a strong plant. There's a lot there to love.
I was considering the name, and remembered that devoted mystery-reader though I am, I've never read what is considered to be the first or one of the very first "mystery" novels, "The Moonstone" by Wilke Collins, which is about a jewel, not a rose. However, in looking it up and reading various reviews of the book and the several television adaptations, apparently the book's detective character is a rose lover--at least he is in one DVD version--so now I'm interested. Maybe now I'll actually read the book; it's available for free on the Internet here at Project Gutenberg, or if you have a Kindle you can download it to that for free as well.