Yesterday I got the 870 Express upgrades in the mail,along with Jerry Kuhnhausens manual,and installed them tonight.Thanks for letting us Express owners know about the upgrades.The only part I did not order was the sear spring,after researching it I felt that the only reason it was stronger was to increase the trigger pull to prevent a/d's under stress in a l/e situation.Was that a correct guess,or is there another reason for your recommendation to install the heavier sear spring?Thanks.