Automatic Litterbox Central

Has anyone tried crystal pearls or any other types of sillica litters with the litter robot? and does it work?
Is the 7 minutes enough for the pearls to dry out a dump?

Asking this because I think sillica litter, if they're fast enough, would work great with the litter robot in theory. Pee won't clump but get absorbed right away (so the litter robot would be "shooting blanks" when the cat pees), but the number 2's would dry up and take little space in the dump.
In theory, you can go without emptying the bag for a much longer time. At least 3 times longer (assuming a cat pees 3x as much as it takes a dump)

(the sillca pearls will looks yellow and ugh for humans, but since cats are colorblind, it wouldn't matter to them. As it's odorless)

I have tried crystals in the LR. Remember, the urine is absorbed in the crystals thus the urine is never cycled out of the LR... And little bits of poop can also remain behind because the crystals don't coat like regular clumping litters. You must also be careful about the size of the crystals... they all do not fit through the screen. So, try it and see what you think. I like crystals a lot (and have a box of crystals on hand for my cats) but went back to World's Best in the LR after my experiment.