That is a great question. The only thing I can say is what I am seeing with my M3 with the 600 mm STX liner in 22.
It shoots 23 grain slugs quite well, the groups open a bit with 24.8’s and when I jump to 27.5’s it is hopeless.
My Maverick 22 700 mm heavy slug liner shoots the 27.5 very well at around 970 fps.
What I draw from this is the STX in 22 probably does well with lighter weight slugs 24 grain and lighter.
That is my experience and others here may have different results.
I am all ears on this as I am trying to decide if I want to shoot light slugs out of the M3 or put the heavy liner in it.