While I have both the G20 and G21 and like both cartridges, for carry I'd prefer the G29 over the G30 because of ammo capacity. Both are identical in weight and size but the versatility of the 10mm over the 45acp as well as the larger round count swamps the G30.
Ammo availability is a non issue for me as I handload all 10 of my calibers. Cost wise, the two are about the same as you can get free 45acp brass but the bullets cost more. Both calibers can be loaded mild to hot, however, the 10mm is far superior as a woods gun where it's higher muzzle energy allow it to be effective over thick skinned game like hogs.
That said, for my basic home CCW piece I chose the G23 as it's smaller frame is much easier for me to conceal. Further, it's higher capacity and the easy availability of 180grn Speer Gold Dot ammo make it an easy choice. However, my HD, night table choice is my G21. In the woods, I carry my custom G20L without the magwell with 17+1 rds of 200grn hardcast handloads.
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