Hey May!
Welcome to TBCF.
Reading your last post, I wouldn't try to skimp on litterbox size. I only have one Bengal. When we got him, we had 2 boxes - 1 covered Boodabox, 1 open, deep, corner box.
He looked so tiny in them to begin with, but now, only the larger, open box fits him when he poos. Quasar is just shy of 9 months old and weighs just over 11 lbs. He likes to sit up tall and hold the edge while he goes.
He pees in the covered one and pees/poos in the open one now.
I can only imagine what trouble he might encounter with a smaller box.
We moved 5 days ago to a larger, 3-storey home and added 1 more covered box so as to have 1 on each floor. So far, Quasar has managed to find all 3 boxes but still only uses the open one for poos.
In summary, with bengal kitties, especially TWO of them, I would stick with larger boxes. Also, you need to have (minimum) 3 boxes for two cats.
Good luck with your beebs!
Sincerely,
Ruth
Ogden, UT
p.s. I am a registered nurse and am, by definition, obsessed with poo.