Ok, I messaged the seller via ebay today with this:-  
Hi, 
  
I have some concerns about the strength of the key blade, would you confirm what material the blade is made from, the last thing I want is the blade snapping off in the ignition key barrel. 
  
Thanks and regards 
  
His reply:- 
  
Hi, 
Sorry am not sure, we sell many blades and as of yet not had any issues with blades snapping!! 
Regards