Changed from the G23 Gen4, to my P239 SAS, about two years ago. Switched to IWB carry at the same time, when I started P/T SRS duty at a local school.
I had almost forgotten how much I like the feel of that 239, and how well I shoot it. The finger grooves on the 23 never did quite fit me, but it still shoots surprisingly well. One less distraction to interfere with grip acquisition makes the Sig just a tiny bit quicker on target for me.