I guess I had bad luck with a box of François Louis tenor reeds I bought a few months ago. They felt too hard the first day, but turned out way too soft after five days of playing.
They are made in the Rigotti 'factory' and I've heard that sometimes the cutting machines are not set up the way they should, hence the chance of getting some bad ones once in a while.
Having said that, they should normally indeed be the best/most consistent reeds around...