As with all Vandoren reeds - a box will contain about 60-70% good reeds.  This is the factor that has led me to investigate other options.  If I pay for a box of 5, I want 5 good reeds. (For alto, it may only be 6 out of 10 that are ready to play (without alterations), and only 3 of those may be really excellent).  But, when I find a good Vandoren, I like it.