I though S1 was wonderful. The art was good, the voice work was really good in the dub, the story itself was exciting, the characters were pretty complex, etc.

I really like how it was split into shorter 4-episode arcs as well. S2 is still really good and has a lot of those same aspects, but iirc it is one longer story and things start to get a little more... implausible, at times with the heist-type stuff.