I have an RS !! in .25 that loves my slugs. Oneshot is correct, using a shorter, heaver spring with give a much better shot count.
I love mine. Was able to source a nice thumb hole stock for it and it is vey nice
I would suggest a Neil Clague Reflex ldc or a DonnyFx. the shroud is virtually useless. Doesn't do much at all. But when a few bits are made for it inside and an added ldc, it is very quiet.
Only issue is with parts. It is much like buying a use car from a disreputable dealer. You buy it, you own it. No factory support w what so ever. None!