The difference between Pharmaceutical Grade and Research Grade is just a seal of approval by a Government Agency (usually FDA). So, IMHO that does not mean that research is low/bad quality.
Ive read a lot about FDA mistakes, enough to know not to trust them 100%.
As TheAttrition said, if you trust the source, go with it.
I am not a doctor nor I play one on TV. This is just my point of view.
Good luck!