Perhaps it should be called St. Andre's Oratorio now that he has been canonized but I'm sure he would be too humble to want this. While not especially old, there is a lot to see at this religious site. In general, I find the interior of the main church actually is the least interesting part - it is beautiful but quite plain. If you go, take in the other portions, or do so on several visits. These include the charming little chapel that Brother Andre originally set up; a museum of religious art (changing exhibits), a crypt church which was obviously completed before the main one and has more traditional stained glass; a hauntingly beautiful hall of votive candles; a way of the cross; a grotto and a carillon. On top of everything, the view is spectacular.
While I am an atheist I did find this to be a very impressive place. I would withhold five stars simply because I do believe that as far as Catholic churches in North America go, I'd rank both the basilica of St. Anne-de-Beaupre and the Cathedral of St. Louis (in St. Louis, MO) as just a bit more impressive from an artistic standpoint.