As for weapons, I'd say wear and tear of heavily tuned weapons should be way bigger. Real life example. Benchrest rifle shooting. Those accuracy freaks use typically exotic cartridges with extreme muzzle velocities and very flat trajectory. (And they shoot so accurate that one needs to measure hole in the papertarget with some measurement tool to differentiate between winners and loosers in competition...)Why do not more everyday weapon hobbyist use such cartridges. Well reason is, that those monster cartridges eat barrel innards as breakfast. After some hundreds of shots best accuracy is gone. After 1000-2000 shots barrel is ready to be scrapped. While with normal rifle rounds lifetime of barrel could be about 20 000 rounds. And accuracy would be nominal for many thousands of fired rounds.
We used 12.5 mm shells with 7.62 mm points in heavy machine guns when I trained with the UN. The trajectories were so flat you hardly had to compensate even out to 1000 m, and the rounds wandered through engine blocks like through butter (almost). The bolts of the guns, however, did not last long. Neither did the vehicles the guns were mounted on - they were shaken apart eventually! We also did some continuous firing drills with light machine guns: One gun per team, 3 barrels and pretty much all the excess ammunition of the year (several 10s of thousands of rounds). Gun mounted in a frame, and you fired at moving targets until you couldn't see the sights for the heat shimmer anymore. Pop in new barrel and set old aside to cool. Switch between 3 barrels that way. Eventually the barrels would warp and/or the gun would start to jam.
So yeah, wear and tear is definitely lacking on engineered weapons. Don't get me started on healing beams...

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