@winters2
I currently own this, purchased from PureBulk. At the time, this was the only seller of riboflavin-5-phosphate that I was aware of. That was at least 8 years ago. I know there must be a shelf-life on supplements, but I keep most everything I buy after the expiration date. I can't find an expiration on this.
I'm sorry I can't provide anything about the quality; but as I say, at the time PureBulk was the only seller of this.