Bought as a replacement for my V911/FP100 because the stock ones were SHITE !!! ABSOLUTELY worth every penny. I ordered mine and got them in 7-8 days. They were well packaged and all accounted for, and fit perfectly. I can't say whether they provide extra lift because I also ordered hotter batteries, thus increasing flight time anyway. I stripped 5 stock gears in accidental power-on crashes, and it would happen EVERY time. There was no margin. These are much beefier and you can see and feel the build quality. I will let you know how they hold up after I fly for a bit. GREAT PRODUCT!!!