HK45, HK45C, USP, USP Compacts already have similar-weight TRS in them (214164) so I don't think this light TRS will change much. It might not fit the P30/P30L series so you can rule it out (one of the legs is too short). Not sure about P2000/P2000SK.
What gun do you have?
I researched a little further and the standard TRS in the P2000/P2000SK (219441) is the same as the Heavy LEM TRS. So I guess replacing the standard TRS with this light TRS may lighten the trigger pull. Also, if your P2000 has the heavy FPBS, replacing it with the light FPBS may help the pull, too.I too am curious about this. I have a P2000 and am wondering if it will make a noticeable difference.