Was my first day out with it and I am glad I picked it up. Was shooting some reloads, 180gr fmj's and 180gr gold dots. The fmj's shot fine, I had 1 FTE with the gold dots which felt pretty warm. I also shot 40 Hornady 180gr XTPs through it without a problem. I then switched to the lone wolf .40 conversion barrel I bought last week, fired 50 WWB 165gr fmjs, 20 155gr critical defense and 20 Federal 180gr hi-shoks I had stashed in the back of my safe.
Its all stock except when I switch out the barrel and I plan to keep it that way for now. I hope to put more gold dot reloads through it at some point if I can score them and see if that one FTE was a fluke or not.
Good news. I ordered my G20 G4 three or so weeks ago and I'm still waiting on it.
Anyway, does the recoil feel different running .40 compared to the 10mm Hordany ammo, etc?
I can't speak for actual .40 ammo, but running .40 level 10mm and the Hornady in my Glock I do notice a difference in recoil.
And the Hornady is a "warm" 10 load, but I wouldn't consider it "hot."