No stick with clumping litter. They may be cheaper to start with but you will own to change it way more often thus it will end up being the same price or even more expensive. Don't forget that cats verbs and bury so the cedar chios may hurt there feet, also they will make a mess of your house as they are muted and will stick to your cats feet.
Answers: Yes it's safe, within fact they sell a cat litter made of hardwood and cedar chips. It's called "Cedarific Natural Cedar Chips Cat Litter". Just a advisory, your cat may not like the smell, I've bought cedar chips for my rabbit and the cedar smell was overwhelming, the bunny hated it and my cats made a obverse when they went near his cage. I haven't used Cedar litter for my cats, but it is 100% biodegradable and can be composted or incinerated, and it is probably a in good health choice than dusty clay litter which is bad for kitty's lungs.
I don't think a cat would use them but I would not even try. We use the wood stove pellets (no chemicals) and that works ably for us. But you would have to use normal litter and then slowly attach the different texture in till its switched over.
Just putting in Feline Pine, or pellets won't work because the cats won't know its litter.
Should be safe, whether your cat will take to it, may be another interview. I use the Feline Pine stuff - and my cats do ok with it. Then I found out that there some stuff called Guardian that is to say sold as horse bedding, that is the same material as Feline Pine, singular it does not smell as woodsy. It's cheaper and does a find job of absorbing odors.