I bought 2 and both motors had rusted magnets. Since I've rewound motors before I opened them up and cleaned the metal filings using masking tape. But most people I know would simply have thrown them away. Even if you're the kind of person who's comfortable opening a motor can you'd still probably throw these away as the C-clip used to hold the motor together are very fragile and mine broke when I opened the motor. I had to fabricate my own replacement C-clips. Most people I know wouldn't be able to fabricate C-clips or know where to find replacement C-clips. After cleaning the rust I spray painted the magnets with lacquer to prevent future rusting.
Apart from the horrible quality control and poor C-clip, this motor is actually very well built. I can only speculate that there's a leaky roof somewhere at the warehouse where these motors are kept that ruined a batch. Once cleaned up they perform quite well.__ Prop/Amps/Watts/Grams of Thrust _____
11x7x3/27A/295W/1380g ___ 12x8x2/32A/340W/1515g ___ 13x6x2/36A/375W/1735g ___ 12x10x2/39A/400W/1265g ___ 11x7x4/43A/441W/1775g