Join Date: Aug 2012
Location: Ann Arbor, MI USA
It doesn't seem like most people have strong opinions about them. I believe Hoppy said Miller's is supposedly more balanced but that he has noticed no difference since switching.
CSM+B has more iron so if you use Millers you might have to dose more supplemental iron.
Miller's has significantly more copper IIRC. Not sure if it would be enough to bother any invertebrates.
Those were the two differences that jumped out at me.