Wow! - No posts for over 1 year?
Well, maybe no one will reply, but:
I've used 2 x R Gacha + 1 x Pero Pudding almost 100 times across 2 accounts and haven't received a Limited SR. (Though I've got the N once on each account and the R numerous times). Just how rare is the SR? And is the 2 x R / 1 x PP really the best method? Another theory out there is just to use 1 x R Gacha only - 2 times the attempts, I guess, but is it even LESS likely?
Thanks if anyone's still alive out there and can offer some info.

I have used about idk, maybe 500 R tickets, and have gotten it 3 times. You just have to keep at it.

Also: only a single R is needed, you dont have to waste extra stuff. All it gives is more salt.