what litter do you use in your littermaid?

hi
I have had a litter maid since december of last year and have been using the
pet smart store brand advanced stuff, but it has recently went up in price.
It used to be 13 for a 40 lb box and now the boxes are 30 lbs and have a new
odour thing in them and they are 16. Which is kind of pricy since your
getting less litter. So I was wondering what other brands are good for the
littermaid. I'm in canada so we don't have some of the same brands as the
US but most are the same. Thanks