Two benefits of the 42 over the 45 are:
1. The tang pin is bigger on the 42.
2. The handles of the 42 are Ti.
The force of the tang hitting the handles is spread out over a larger area with the 42 because of the larger tang pin. Due to this you will not see the handles wearing out so soon.
Also, the Ti is a much harder metal and can take more abuse before showing any signs of wear.
The combination of the two will make your 42 stand up to a lot more and last longer.
After a few months of heavy use on my 45, I could see the areas that the tang was wearing into the handles. It was mostly on the safe handle, because that is the one you are holding most often and takes the most force. On my 42's however, I treat them worse than I ever did with my 45 and they are holding up very well.
It is of course a disposable product, which means that eventually, with enough wear and tear, you may need to dispose of it and get a replacement.
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John
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