I just purchased a Wolff Type 1 shooters spring kit for my Model 10. The first problem was that the "standard power rib" spring didn't even fit in the frame. I decided to go with the 14# rebound spring with the factory mainspring and see how that felt. The 14# spring left the trigger feeling sluggish. I understand why this happened and that it is a compromise, so I decided to bump up to the 15# spring (heaviest that comes in the kit). This felt really good and the return was better/acceptable, but it allowed a little pre-travel/creep in the DA stroke that I didn't notice with the factory spring. I can live with a little bit of creep, but overall the kit was a disappointment. I understand that I bought the kit to try it out, but hindsight being what it is I could have saved some money and just bought the 15# rebound spring. Anybody else have this trouble? P.S. I'll be contacting Wolff about the mainspring not fitting. They have a great reputation and I'm sure they will correct the issue. The rebound springs is my decision/fault, so I accept the blame for that.