Pros and cons of coupling vs. threaded when transitioning from copper to PVC
Even a properly installed threaded copper x pvc connection will eventually have problems due to the differing rates or expansion/contraction + plastic embrittlement as it ages. That is not to mention that rarely is a plastic x metal threaded joint properly done to manufacturers specs. The plastic usually gets over tightened into the metal, leading to an even faster failure of the joint.

None of those are a problem if you use a properly rated no-hub coupling. No-hub couplings are simpler to use, faster and less prone to failure.