I've never grown or seen Purple Maze so can not say how it would do in zone 4, either in the ground or potted. I have never tried overwintering daylilies in pots, maybe someone else will help out here with ideas and how to avoid problems.
I grew Patterns in Time for 5 or 6 years, no special care, it grew and bloomed well, nice daylily. The base colors of them are different according to the reg data as you may have seen when checking the database. Purple Maze as medium carrot orange and Patterns in Time as cream.
