I'm thinking about smoothing out the internal parts of a few of my older N-frames (Models 27, 28, and 29). After watching Jerry Miceluk's DVD ("Trigger Job"), it looks pretty straight forward. My question is...after stoning the metal parts, Jerry replaces the mainspring and trigger return (rebound) spring, and files down the cylinder release (bolt) knob, because he's shooting competition. Should I replace the springs on my N-frames even though they are not going to be competition guns, or leave the stock springs? Clark Custom Guns sells the spring kits for $17. Thanks.