actually, if you examine the stock back closely there is a space between the cover and battery big enough to fit the 0.5 mm receivers into. I really think Sammy is just adding the electronics to the stock cover and it was designed this way from the start...still a bit puzzling why they just didn't include it in the phone out of the box!
With the aftermarket receiver, your concern should actually be more with the "fit" of the receiver as the cover gasket runs dangerously close to the charging contacts and leaves little room for extra backing material in this area! Be careful when choosing an aftermarket receiver as many leave extra material that will interfere with the seal! You may actually be able to trim this area back if necessary, but your taking a chance!
Personally, I ordered one from DX that seems to be trimed VERY close to the contacts and is a "slim" 0.5 mm model and is only $9, so if it doesn't work is is no great lose!
Down the road I may order a new Sammy charging back when they come with new collars to change the color of my phone...Red sounds nice!
Also, with my S4 I had no problems with the aftermarket thin receiver and any of the cases I have including several TPU and Spiegen Neo Hybrid or Slim Armor!
And adding a higher power 2a wall plug tends to cut charge times considerably!
Cheers