CVTs generate ridiculous levels of irrational hatred amongst "car guys." This especially extends to "journalists," who are disproportionately influential. Manufacturers have even taken to programming their CVTs to include fake shifting so they will "feel" more "natural," bowing to this perceived dislike. As if there's anything "natural" about a transmission.
Subaru extended their CVT warranty, as far as I can tell, to help allay this rising tide of irrationality, not because there were actual issues beyond statistical norms. All transmissions of all types and from all manufacturers will exhibit occasional problems.
As YoGeorge points out, the best available source of statistical data for automotive reliability -- Consumer Reports -- has shown Foresters to exhibit very goord to excellent transmission reliability in the years since the CVT was introduced. Even in years where the car had other problems that dragged it down, those weren't transmission-related.
Even the "professional" reviewers, at some point, usually say, in effect, "I hate CVTs, but Subaru's is actually not bad."
Me, I like it, and my 7-year old CVT has been flawless, and contributes to both smooth driving and excellent fuel economy. It also adds a lot to the excellent performance of the Adaptive Cruise Control, which never has to shift gears. Even a normally smooth conventional AT can seem rough when shifted by a cruise control.