Our store had many of the specialty grapes on sale for $2.99 a pound a couple of weeks ago so I bought a small amount of Cotton Candy, Midnight Beauty and Moon Drops. I was inspired by this thread to experiment.
The Cotton Candy grapes were interesting, but overwhelmingly sweet and the flavor seemed short-lived. The first bite gave the taste of lots of sugar and the odd, candy flavor but then it quickly became vapid. They also seemed to get soft quicker than the other varieties, which I don't like. I won't bother with these again.
The Midnight Beauty grapes were very attractive and stayed the proper firmness. The flavor was good, much better than some of the older dark grapes. Nice overall grape. I'd buy these again if they are on sale.
I loved the Moon Drops! They are pretty sweet as well, but the flavor is much more complex than that of the Cotton Candy grapes and remained enjoyable from start to finish. The shape is amusing, as well. I would definitely buy these again. Yum!
I'll be keeping an eye out for new varieties to try.