What Chief38 said !

In addition to reading Lovette , also read Grant Cunningham.

I will pass along what I learned from observation : On a typical qualification COF , going from a K frame to a J frame , will lead to a group ( pattern ?) Size of at least 50% larger , often aproaching double. If a shooter typically chews the X ring with normal revolver, then will still do respectably with a J frame. If a shooter is kinda average ( mid 80% score ) , they will drop to around a 30% score. ie lots of shots not just missing generous human sized outline , but also missing the paper entirely.

If you take as fixed the use of a J frame , and vary the grips for maximum comfort/ control, then Compacs are a good choice. BUT if you set the parameters the other way around a K frame) with Boot Grips will be about the same , or smaller than oversize J grips. And I can shoot a 2in K Frame way better than a J frame.

A J frame with Magna or Boot grips is superior for pocket or ankle carry. For IWB or OWB , I'd rather have a 2in) K frame .