I just started co bathing about a week ago, he's nearly 3 months. He LOVES it because when I'm right there with him I can put him deeper in the water and hold him while he kicks and splashes. He loves being as submerged as possible and I'm really only comfortable doing that while co-bathing. I still use the baby bath if I don't need one, and he likes it but nothing like the big bath! We also use the sink sometimes if there happens to be no dirty dishes in there. Doesn't happen often since LO was born...