I do not use NOW products myself -- just a personal choice regarding brands, however, for what it may be worth, I can contribute a little something to this thread.
I am a member of ConsumerLab.com and while NOW is not always tested for each product type, each time that it does appear on items I check or reports I receive, it has always been on the 'approved' list -- meaning that Consumer Lab found it to contain the proper ingredient(s) and in the specified amount(s).