I was gifted two blocks of gianduja, a Callebut milk that was opened with a best by date was in March, the other a Valrhona dark with a packaged date of july 2014 and a best by date of July of last year.  Should I toss them?  The Callebut seems fine.  

I have a hard time finding gianduja so this is a big deal.  I usually make my own,