Congrats on the G29!!
My personal preference
is to swap out the OEM bbl with a KKM IF I'm going to shoot and reload high pressure rounds. Why? KKM's fit great out of box, they have good case support, shooting HOT loads in them... no smileys. Shoot same load in Glock bbl....I get smiley (sheared case head).
For example, I shot Underwood 180g XTP's in my Glock bbl...case was wasted d/t moderate smiley. Then I swapped in my KKM (same length) and shoot the same UW load/same box and didn't get smiley. (I can reproduce this easily on hot loads.) Also, I haven't seen any complaints about KKM like I've seen in other AM bbl manuf.'s.
That's MY experience and why I make that choice. Based on that, you can make your own judgment. Now if you're going to just shoot warm, real 10mm power loads and reload those cases warm or less, the stock Glock OEM bbl may be just fine. Again, this is my experience/opinion. Others may/will argue otherwise.
Just to be clear, a little case 'bulging' is normal from glock bbl's. I see them on cases of factory loads and in .40/9mm, as well, and can be resized/reloaded prudently. But 'smileys' have a distinct arc'd line
that you can often click your finger nail over. If that's the ...ahem....case, definitely TOSS those!
(and reconsider your bbl and/or load pressures) Besides, if your new to reloading 10mm (or ANY round), you shouldn't be loading max charges anyway... IMHO.