I agree 100% about Quest being a good organization. We (Airnet) used to fly their cargo until Quest figured it would be more beneficial to take care of their transportation needs on their own. After I left Airnet, I looked into them. If the location were more favorable to my family, I wouldn't have thought twice.
I have no actual hard evidence whatsoever to back this up (I haven't researched them outside the flight dept), but I would bet that Quest Diagnostics is a solid organization all around.