Ah, the G19. I have a G19 and a Sig 239, and I frankly shoot and carry the G19 more. I am not married to any brand, and I see flaws and strengths in all of my pistols. I have a CZP01, and for years I carried an HKP7M8, love my 1911s, etc. For a long time I rejected Glocks, but the G19 (quickly followed by a G20) changed my mind. The G19 is an excellent pistol.
The difference between the 239 and the G19....they are essentially identical in size. The G19 holds several advantages, specifically lighter weight and higher capacity. The other advantage for me is the lower bore axis of the Glock. The Sig has the advantage of superior factory sights, superior trigger pull, and a better overall build quality, particularly the magazines.
The single biggest downside to the Glock family is the trigger pull. It can be improved, but it still takes some getting used to.
If you are used to -and I would expect you are as you have a pair of Sigs already- the way Sigs point then I would probably stick with the Sig family.
The good news is you really aren't going to lose no matter which pistol you choose. I don't need to own both a Sig 239 as well as a G19, but I am not selling either one. Handle the G19 and the 239 side by side in a shop and make a simple gut choice.