Bath or shower every night here too. Part of our bedtime routine, plus the boy gets spit and sicky and food everywhere (especially in those dreaded neck creases).
Harry gets sooo relaxed and kinda in a trance lol, especially if it's a shower (I think it's the combination of the hot water, the skin to skin contact, and the noise). I showered with him for the first time a couple of weeks ago and it was so lovely. He doesn't get slippery cos we don't use any soap.
It changes often how we wash him though - sometimes DH or I shower with him, or we sit him in the baby bath on the change table, or he lies in the big bath on his towelling thing, or I bath with him