My DD goes to a Steiner School and she loves it. In response to a PP, there are ethnic minorities at the school and they enjoy it there too. The school doesn't have the teachers or equipment to cope with severely disabled people and are open about the fact they can only manage a limited number of special needs children so review applications from them on a case-by-case basis.
Academically her school scored the best GCSE results in the area last year, and always achieve above average. The local 6th form college (especially the Physics tutor) love the children from her school because they have a love of learning and thirst for knowledge, and an ability to think for themselves, because the school does not teach children to pass exams, but to enjoy learning. I can't find the reference but down south somewhere, one of the universities will allow Steiner-educated pupils on to it's Physics Degree course without Physics A-level because of the way those pupils have learned to think. (Incidentally I had an interesting conversation with the science teacher at DD's school (he has a PhD in Microbiology) as I love science and hope that DD grows to love it too).
In common with other schools, DD's school has a racism and bullying policy which is applied.
Sports facilities are limited within the school due to space, but they do manage lots of gym, tennis and football, plus the outdoor play area has lots of climbing equipment. Pupils at the school have competed at County level in various sports including fencing and swimming.
As an aside, Bethany Woodard, British Paralympian Medal Winner, went to a Steiner School, as did Kenneth Chennault, the CEO and President of American Express, whose skin colour happens to be black. Both of them speak very highly of their time at Steiner Schools.
BUT I WILL PUT IN A BIG PROVISO HERE. Visit the school, have a look at the young adults that it puts out into the world and make your judgement from there. DD's school turns out a very high percentage of incredible, bright, curious, polite, enthusiastic and confident young adults.
Yes, it can be scary to think DD will be learning how to cook on campfires, climb trees, build dens and knit, whilst other parents are boasting that their 7 year old can read Shakespeare and score highly on SATS, but I think that Steiner education needs to be looked at long-term. It's about the end-product, not short-termism.