Oh, BTW, that pic of my 4013TSW? I remember when it concerned me at the time. Fortunately, one of the factory guys was at our agency teaching one of our update classes, and I had a chance to bring it in to show him. He said in his opinion it was normal, and that he had a couple of 4003TSW's with the same or more wear in the same spots ... and his guns had been showing that amount of wear for the last several thousands of rounds apiece, since they the 3rd gen .40's he used for weekend competitive shooting.
Now, I've presently got a CS45, my own personal gun, which is starting to exhibit some deformation of the R/side frame camming should. It's always had the usual "chewing" in the front of the cam cut, but now the top is starting show some
lifting at the front of cam surface. Eventual work-hardening of aluminum, and some deformation shifting of the metal from the barrel lug slamming down and against it? Dunno.
Since everyone I knew at the factory who had years of experience in building and repairing these guns has since retired, I'm not sure who I can send any pics to, to ask about it. I can't say how long it's been like that, for sure, either, as I only noticed it under the bright light of the magnifying lamp while cleaning it at my bench a while back.
I've tried to estimate how many rounds I've fired through it since I bought it in '99, but it's difficult because I don't log round counts. I just kept running guesstimates of use based upon remembering how much I was shooting the various guns each month, box & case-wise, so to speak. The first year I owned that CS45 I think I flew by 2500rds in familiarization shooting. Since then it's been my frequent 'range beater' .45, too. Sometimes more than other times, over the course of a year. If I had to guess, I'd put the round count at somewhere between 15,000-25,000+/- rounds.
Well, I remember a repair tech explaining that we'd see more shiny wear on the steel frames of our 4566TSW's (and aluminum wear on the 4513TSW's) on one side, than the other, due to the way the barrel torques to resist the bullet's passage and drops down onto the top of the frame. He said the barrel would hit a bit harder on one side ... and I think it was the R/side? If so, that might explain why the R/side cam lug cut is starting to lift a bit. It was being hit harder by the R/side barrel cam surface?
So, I guess the question is when will the wear reach the point where it interferes with unlocking and locking, and the overall "timing" of the extraction, ejection and then feeding & chambering parts of the cycle of operation? I was told that if the cycle of operation reaches the point where manually cycling the slide exhibited roughness, like gravel being in it, due to the uneven engagement and release of the barrel from the frame cam cuts, the aluminum frame has reached the end of its service life.
A good friend - another S&W armorer from a nearby agency - had that happen with his hard-used 4013 (single stack .40 on the .45 frame). he sent it back to the factory and they told him they didn't have anymore 4013 frames, so they offered him a replacement of another model of similar value. Maybe if mine reaches the point where functioning is affected I'll contact S&W and see what they say. I wouldn't mind a Shield 40, as that's on our state's stupid Roster (the .45 isn't, since it's a newer model that wasn't in production when the Shield 9/40 models were added to the Roster just in time to mist being affected by the micro-stamping requirement that was ordered enacted by AG Harris in early 2013. Sigh.
Anyway, I'll post a couple pics of the CS45 and the cam cuts in the frame, just for entertainment purpose. I have a 4513TW that I ordered and bought at approx the same time as the CS45, but it doesn't exhibit the same deformation of the R/side cam cut. Of course, it's both a larger gun, with longer nested recoil springs, with less violent recoil/cycling ... and I haven't made the same effort to wear it out. (I used my
issued 4513TSW for that for several years.

)
The pics:
Left side (normal)
Right side (slight lifting of front)
The edges appear even when viewed from the top (notice the heavy marking from the barrel dropping onto the top of the frame on each side, though, which has been happening for more than 20 years of shooting)
I'll probably back off a bit on my efforts to wear it out as a range beater/retirement weapon.
Might wait until -
if? - the frame wear reaches the point where cycling appears to be affected, and then send the pics (and the gun, if they'll look at it), and see if they'll replace it with something else, since I'm the original owner and it was a LE gun, and now a retired LE gun. Who knows?