OK, a bit late for the OP as he got the screw out. But, just in case anyone else stripped their screw......
Evidently, the screw is not made of the hardest of metals. Combined with the fact that , at least on current production, a significant amount of loctite has been applied, it's not hard to strip the screw out.
Researched and found suggestions for soldering irons, dremels, drilling etc. Too easy to do real damage. Tried cutting a slot, but again, slightly wrong angle and can cut what you don't mean to. Besides, how are you going to get a good angle to use the slot effectively.
In the end, took the original 3mm T type allen wrench I had tried in the beginning.. Placed the lower upside down on top of a padded vice, spread open enough to clear the ejecttor and hammer.
Inserted the allen key into the screw like normal. Gave the T handle about a dozen firm hits with the hammer (not too hard, use your common sense). Now the T allen wrench had plenty of 'bite'. Took that screw right out.
So, my suggestion, if it even STARTS to strip the screw, just give a few taps with the hammer and you should be good to go.
You all provably know thos already! but thought I would share just in case.
