Yeah, I have those. Only works when there's a stump left over. With a flush/flathead/countersunk screw, there isn't much left at all when you drill the head off.There was a thread (I think on Arrma Forums) about screw extraction and someone pointed to these. I haven't gotten to try them out yet.
https://a.co/d/g9yQvHF
View attachment 213359
If you have something to grab on to, they have a pretty solid grip.
Maybe drill the center, then you have a stud. Then you grab the stud with these? I did this with some Vise Grips on a stock mount that stripped out. I'm sure these will work better than Vise Grips.
Could try an ezout. I've used those with M4 grubs with great success:
https://www.amazon.com/dp/B000Q60UOO/
But, I typically just grind a slot knowing it's going to ding the chassis a bit and move on.
Then use a standard bit to get them out. I have a cut down square edged bit that I use for these that works well: