The Mirella tights are 87% tactel nylon/13% lycra, and have a gusset in the crotch, so they are very comfortable and form-fitting. But the seams around the gusset began to tear almost immediately. I returned the tights as defective and tutu.com sent me a new pair.
Unfortunately, the replacement has the same problem. The seams around the gusset are not reinforced sufficiently, causing the gusset to begin to rip out under the most ordinary conditions (a/k/a, ballet class).
It's too bad, because they are, as I said, very comfortable.
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