Atris and Prodigy are similar - everyday skis with a jibby side to them that appeal to that kid who used to be a park rat, kind of grew out of it, skis the whole mountain, but can't escape their inner 16 year old that yells "SEND IT" in their subconsciousness. I ski the Atrises, and really didn't expect to like them since I usually like a stiffer, more-business-less-pleasure sort of ski, but these are plenty stable for chargier skiing and I've really come to appreciate their surfier powder performance and I think they're really well balanced in the air. My boyfriend picked up a pair that he hasn't skied yet, but he usually gravitates towards a really playful ski (like his true park skis and Bent 120s), but decided to add the Atris since it'd be a little more dependable underfoot at high speeds/on chundery snow. My sister-in-law is on the Prodigy 2.0 and has similar things to say about that line - she really likes that they can perform on the groomers, float well, and pop through the trees super easily.
Legends are a more directional, stiffer, with a flatter tail that really locks you into the turn instead of the surfy, easy release of the two above (they're twin tips). I skied the Chams (their predecessor) and helped my brother buy a pair as well. They carve insanely well, and were a really great fit for my brother, who skied a lot of east coast piste, moved out west, and wanted something that felt familiar but was fully equipped for west coast snowfall. If you're doing a lot of flipping or spinning, the other two are better balanced for that kind of skiing, but if you're just doing basic side hits and cliff drops, the Legends are just as well equipped.