120/month per user would be something along the lines of 1.3/visit (assuming ~3 articles on average every day of the month). That sounds very high?
I wonder how much such big organizations spend on selling advertising (I'm now conflating with the likes of NYT that has ads in its paper version etc). If one truly went for ad-free, one would of course let all the ad-selling staff go (or let them do something else).
I did a back-of-the-envelope-style calculation at one point (I can't recall my source data anymore now though), and basically you'd need to pay something like $120 a month for websites to end up with the same amount of cash as with ads.