If it's not acting up I see n o reason to change it. You will hear the two camps pounding the drum for and against the shorter guide rods. I have both and I have not seen any real difference. Other than the two piece rods needing a tool to take down a weapon that was designed to be taken down without tools.
I have not owned the P14 but do have a P16 and LTC. The P16 has the short rod and the LTC has a full length rod. The LTC can be a little tricky with it's one piece full length rod. The P16 is a tack driver as it is so I never seen a need to change it.
If you think about it there is not a lot of room for that spring to go anywhere under the slide. One might see signs of wear a little faster with the short guide rods being you do get a little more movement but honestly I can't see enough of a reason to change to anything that is not in the weapon as it is. I do however tend to use 18-20# springs in my 45's. Does it help? I do seem to see some difference in some lower end 1911's with the lock up and the heavier springs.
Bottom line if your pistol is working fine as is I don't think you will see any real difference with a full length guide rod. THey are not a real expensive mod though. Try it and see what you think.