I wasn't at all sure so I've just taken two LP53s out to the workshop and tested them together. I don't know whether its a fair comparison as I don't know if all other things are equal but I was shooting more accurately with the unmodified pistol which was a bit surprising.

As far as the Predom goes, I 've cut down an HW30 spring and made Delrin top hat & spring guide. Previously it was doing 300 fps and now its doing a steady 470 fps !! The Delrin machines really easily and its so quick and easy to make these parts - don't know why I've never done it before. If only the Predoms had the Walther trigger.....

Steve