You fell victim to marketing. Full ceramic bearings tend to shatter. They aren't suitable for high impact applications, and just plain expensive for everythin

You fell victim to marketing. Full ceramic bearings tend to shatter. They aren't suitable for high impact applications, and just plain expensive for everything else. Hybrid ceramic bearings (ceramic balls, steel races) are cheaper, but the races will wear out at the rate of steel, so they are an expensive option that needs to be maintained. Your best value if you want fast bearings is to clean out the grease and replace it with something lighter like sewing machine oil or Bones speed cream. The downside is that you have to maintain it more often because oil doesn't stick around as long as grease does. Also, the difference between ceramic and regular bearings is on the order of 1 watt. You'd save way more time in a BMX race by wearing tighter fitting clothes, and if you are doing tricks instead of racing then ceramic bearings on a BMX bike makes no sense.