I bought an MS660 crankcase from Huztl/Machinesdoctor and it had some corrosion on the mating surfaces. After trading emails and pics they still insisted it was paint overspray. Being in the aviation industry all my life, I'm very familiar with what corrosion on an alloy looks like and can absolutely be sure it's not "paint". Anyway, I've not ordered much from them since. I've ordered a boatload of stuff from Huztl and was disappointed that they were unwilling to do anything about it. Other than the corrosion, it looked fine quality wise.