I have a Gen3 G23 with the LWD 40-9mm conversion and LWD 357 Sig drop-in. It shoot all very well with the proviso that it prefers at least a 124g 9mm bullet (with 9mm mags of course). No other mods. BUT... I carry it with the stock G23 40 S&W barrel in it. Because of legal reasons if involved in an SD situation. I live in AZ and if the cops don't charge you, there is no civil suit. But I still keep it legally conservative. This is just something to consider if you want a third party barrel for EDC.