Ishimori Wood Stone Reeds experience?

Hi,
I´ve bought a box of 5 Wood Stone reeds nr. 3 for tenor sax.
I was blown away! I thought: "OMG these are the best reeds by far! These are MY reeds now" I loved them at the first note.
The problem came when I bought the second box of reeds. They are way harder than the first. Both are number 3 but the 2nd. box are like 3,5 or more. I can not play them.
I wrote to Ishimori and after several mails and weeks they told me that this difference is normal. But this is not true.
I play sax for 30 years and I know this little difference in one box of reeds, but no, in this case there was a printing error or something like that, the 2nd. box is almost unplayable.
Have anyone of you experience with these reeds?
Should I buy a 3rd. box?
These reeds are really expensive, the cost the double of Vandoren or Daddario.
Thanks in advance.
Regards,

Mariano
Tenor Sax J.K. SX90R Black + Theo Wanne Durga3 9 metal