Pros
At least in the early days of GRAM, you would get to wear a lot of hats and gain experience fast. With other pharma companies, entire departments would handle each individual facet of the company's business. At GRAM, they would have several departments' worth of responsibility shouldered on individuals. GRAM is to your resume as the hyperbolic time chamber is to Goku's power level.
Cons
You will not have the procedural structure found at most other pharma companies, so beware if that's the type of environment you need. GRAM also pays quite low. They always tell their employees that the pay is competitive "for the market," ignoring the fact that they are only 1-2 other pharma companies within 45min. This was made significantly more obvious once Covid hit. The ability to work remotely emphasized how much could be made elsewhere without even relocating. Finally, GRAM has terrible office politics. Entire departments are crippled by middle-schoolesque bullying and gossip. They will tell you that you are family (GRAMily, I wish I were kidding) but I think everyone has certain family members they would rather lose contact with.