Downsides, yeah, and when there are more downsides when churches first start - they go through stages of transforming to becoming multiracial. So in the beginning stages there's often a lot of pain, a lot of confusion, a lot of people leave.
I never meet a church that wishes they didn't do it. I never meet a leader that wishes they didn't do it. They will all say, to the person, it's hard. It's difficult. It comes with complexities and confusion as you're trying to go across cultures, and you don't understand, you didn't mean to offend somebody but you've offended somebody. But they will all say it just does something.