Sorry, I mistakenly voted no because I thought it was a wand of cold. Please, mentally subtract one "No" vote and add one "Yes".
I think a guaranteed ring of ice is not needed. On the other hand, a guaranteed wand of cold would prevent being forced to quite a lot of grinding in some games (yes, I know the druid gives you frost bolt, but with some characters it's unwise to go with the druid and at the point where you make that decision you don't really know if the RNG is going to throw a wand of cold at you or not).