12g gun clubs are interchangable with STS.
20g seem to be also.
Case won't last as long as STS but a LOT better than new AA (IMHO).
Only slight difference is that the head of the shells are steel (sometimes brass plated). works just fine and easier to resize than AA but not quite as easy as STS.
I pick them up by the bucket full at the range and use them as throw aways with my gas gun as well as with the O/U.
Never had a problem with them.
I also load STS/Nitro/(old)AA hulls to same low pressure recipes and they all perform the alike. If I don't look at the shell before I fire it I can't tell which one I used.
