The real problem is, it can change any time. PS4 can become more stringent, and XBox One could become less (well, in theory).
I'm not sure I trust Sony not to be an asshole regarding DRM. It doesn't have that good a track record. It is a good bet the moment the marketing hype dies down, and the stock holders start pressing, they will tighten their DRM.
"The pyramid is opening!" "Which one?" "The one with the ever-widening hole in it!" -- The Firesign Theatre