Slow Fly Prop- I went too cheap!

Having depleted my stock of APC slow fly 10* 4.7 props on the Extravaganza I thought I'd save a bit and try a HobbyKing 10*4.7 4 pack ( probably for drone use) What could go wrong I thought, a prop is a prop and the difference in performance would be marginal surely. Wrong!. The HK props must be loading up the motor significantly because after each flight today the lipo packs were almost too hot to touch and the props are also much noisier than the APCs' So back to the APC's for me I think and thanks Chris for the loaner, I'll get one back to you when I get my order in.