Taken from
Lower Mana Cost - UOGuide, the Ultima Online Encyclopedia
"Publish 81 introduced Armor Inherent Lower Mana Cost. Each piece of non-medable armor will provide LMC with the exception of woodland armor. Each piece of armor (up to five pieces) will provide a small percentage of LMC, which is not subject to the item property LMC cap of 40% and is neither shown on the item itself. The armor pieces which provide the most LMC will take priority (see list below):
- Studded leather, hide armor, stone armor and bone armor provides 3% of LMC per piece
- Platemail, ringmail, chainmail, and dragon armor provides 1% of LMC per piece
- Medable and woodland armor provides no inherent LMC.
Thus, as of Publish 81, a character covered in 5 pieces of studded leather can reach an total 55% LMC."
Essentially, if you can spare the 250k fee per item, remove it if you want the potential of an extra 15% LMC. On a more casual playstyle basis, you probably won't notice the difference too much.