Pros
The best reasons to work for this company are the people, both union and otherwise. The opportunity is there to create cultures, if you are strong enough to do it. The opportunity is also there to bring the company into the modern era with regards to inclusive policies and procedures, but beware the storm those changes will bring.
Cons
The downsides to working for YRC are often the downsides to working for any transportation company; an entrenched mentality which sets an adversarial tone between management and labor. I experienced other issues with the company but they dealt with particular people and not as much with a particular mindset. You can expect to experience some form of ridicule and verbal ugliness on team calls, and you can expect to see the promised collegial and team based support systems evaporate at the first sign of a downturn in an operational metric. Expect to stand alone. As was memorably told to me when I first accepted the job, if the phone isn't ringing, you are doing okay.