We've used both, but never had an odour problem with either of them - but we had girls, who I believe do not display the same levels of smell as the male version

Is it males you have?
We had three girls and the litter was changed every two to three days.
I'm not aware either of any other paper based litter safe for ratties in the uk, I'm afraid.
If you could get them potty trained - we had the girls poop and pee in a dish full of litter in the corner of the cage (okay, they still wee'd in their bed

) - it's easy enough to tip out and renew daily, which might be a solution.
Good luck, let us know how you get on.
Aileen
and Lilith Ratson