i was using clumping and had to switch to clay when lola came home with me. i just switched them both, because lola likes to use big kitty's box. actually, it's quite devious... she poops in it and then pees in hers so it's nice and clean...
vet told me the same thing, clumping litter is dangerous when injested. it's actually no more work. i still scoop out hard stuff, and change once a week. they seem to really like the larger texture, anyway.