It was very friendly and we had very good communication, they asked a bunch of question, their salary is good to be honest and you don't have to worry about everything.

Extremely long and burdensome process with lots of irrelevant questions and tests that consume way too much time of everyone involved without bringing much real value in return. It starts with a long form that asks even your GPA and gets down to your familiarity or sympathy for mathematics. Frustratingly long and cumbersome.