[cousinmark]

For EDC I'd suggest staying within the interval Kimber suggests. I can't quote the suggested interval for an Ultra? It's better than the 1k for PRO sized guns. I'm pretty sure they advocate the entire set up, guide rod and all be replaced. Having been through the adventure with the Micro .380 recoil spring changes, I'd also suggest not trusting a new rig until you've run a few hundred rounds with it. If the factory rig works well in your pistol stick with it.
JMO...