It depends really, although Kimimaro seems to work a bit better
Kidomaru gives himself shield each turn, which is nice, and also raises his defence a bit with each damage caused to him. Kimimaro at 3* gets higher boosts though, with the same passive, and can dodge a lot. My recommendation is using Kimimaro with someone who can shield the guy, Kabuto for more often triggering the curse mark passive, and most likely your main (if you are Earth, then you can give shields, so you have one slot for your creativity)