Does radio room in Fallout Shelter always attract the same kind of low stats dwellers?

Question

I've been running several 1-slot radio room for a while and I only get dwellers from the wastelands whose SPECIAL stats sums 12

From time to time, one stat peaks to three instead of the usual max 2 points but it is still a 12 SPECIAL dweller

Should I always expect this? Do stats depend on the quality of the room/broadcasters or it will always be the same no matter what I do?

I am not asking about getting legendary or rare dwellers, it's just that if it's always as it's happening on my case. I have for example a +1 SPECIAL pet to newborns, maybe there could be a way of getting better stats for attracted dwellers

Answer 1

The Radio Studio (wiki link) has nothing to do with the quality/level of the dweller that shows up. That's a random attribute, with of course the higher level/legendary characters being much more rare. What the Radio Studio does do, however, is increase the chances that a dweller is attracted to your vault. Basically it just speeds up people coming to your vault door. That's really it. (Well and it increases vault happiness too, but that's unrelated to dwellers showing up.)