That might work, but only if they know the specifications/parameters necessary. Is it simply a matter of voids, improper and spotty heat treating, something else? Only S&W could reliably determine if there was an issue based on their test procedures. I like the idea of just sending the cylinder back, especially if it is of a concern. Offering a whole new gun is mighty generous of them, especially since a lot of 624s were likely acquired on the secondary market and used hard already. If you like one of the new guns, and the free IL doesn't bother you....
. I don't think you can buy an old Ford Escort Molotov on Wheels and expect a new car, now, can you?
I'm just glad the serial number of my LH 3" is in the AL
WXXXX range!