Pros
JCL has some of the most intelligent and hard working scientists that I have ever had the pleasure of working with. There is also a very strong sense of community within the lab and the lab manager is extremely intelligent, kind, and willing to listen. The fact that it's a very small company really allows one to gain experience especially around GLP and government regulations of pharma. 12 holidays a year is nice.
Cons
Don't be fooled by some of the reviews on here, this place has very VERY long hours. Plus most people are salary so overtime is not paid. Sometimes it was eerie since the entire building is always deathly quiet, and I'm not sure if that's just the culture, or nobody is allowed to talk. Upper management is horrible and tends to get in late and leave early, which only decreases the already poor morale (especially since flexible hours are not permitted). Morale is easily the lowest of anywhere I have worked. During my entire time there, the turnover was extremely high, which always led to questions about the stability of the company as well. Any idea is a bad idea unless you are management, since they refuse to listen and are extremely stubborn. The review saying management "has the mindset of 'we didn't need you anyway'" hits it on the nose. It's almost like staff is considered an object instead of a person, and everyone is replaceable. Pay is extremely low for the industry, but I think that is more and more common with CROs.