We love our littermaid box but probably would never have spent the $$ for one if I had not gotten pregnant years ago. We're on our second box now but it's so worth it though. One of those things I didn't know I needed but wouldn't live without now that I have one.
I've used most litter brands. I prefer Fresh Step Multi-cat but that's only because one of my cats won't use the littermaid litter. He's our oldest, and pre-littermaid box so he knows when we change things. After a few weeks of him using the spare box downstairs after we filled his with the littermaid litter, we poor humans finally got the idea and went back to fresh step before he mounted further protests.
Having used many different brands, I do think that, even though the littermaid litter costs more, we used less of it and the cat box scooped faster/better with that brand because it is lighter. A friend who uses LM seconds my opinion that it's some of the best litter she's ever tried for mutliple cats and said she used less too when we discussed it a few years back.
When the motor on our first box broke years ago, I called them and was told that sometimes the other deluxe litters are heavier and cause stress on the motor after awhile. It makes sense to me because I have noticed how slow the scoop moves at times using FS, and especially Tidy Cat, along with some other scoopable litters, but they do work and are more reasonable in price.