I tasted milk replacer years ago and as I recall it had a slightly metallic taste, no where near as good as it smelled. From the smell, I was expecting it to be sweet but not so much.
It was like coffee to me, smells so much better than it tastes, lol!
I need to see pictures of your new baby, OP! I love calves, taking care of them was my favorite part if my job(except for the bucket training, lol)!