I'm not sure there is enough room on this page. If you read through all the reviews for CSX on Glassdoor, you will notice a definate pattern. Those who work in an office type environment or regular hours (Mon-Fri, 8 hrs a day) tend to have a favorable opinion of the CSX. Those who work in the Transportation Department -T&E (Trainmen and Engineers), as I do, almost always have a poor opinion of CSX.
At any rate I've been with CSX for 10+ years. I have never in my life worked for a company where there is so much animosity between management and the frontline labor force. It is definately a hostile, them against us environment. These flames are fanned on a regular basis by poorly qualified low and mid level managers.
The hours are long and unpredictable. 12 hour days are not uncommon and you will most likely be on call 24 hrs per day. With the exception of yard jobs, you will seldom go to, or get off work at the same time. You may get called at 23:00 and be expected to work till 11:00 the next morning. The next time you may be called to work 11:00 until 23:00. It is a NEVER ENDING case of jet lag. Depending on the job, you will likely get 1 day off per week or 2 days off every other week. It is unlikely that your day or days off will include a Saturday or Sunday. Again unless you are working a yard job, there is no such thing as a holiday. Trainmen (Conductor) and Engineer jobs are seldom beneficial to ones health or relationships (spouse, family and friends). You may think that all that travel and rail riding sounds fun and exciting, but going back and forth between the same points over and over quickly becomes monotonous/tedious.
I could go on with detail after detail about the "cons" but I think you may be getting my point. Over all if you are considering a job with CSX, look for one with regular hours and days off in a department other than Transportation. Avoid Conductor and Engineer jobs.