If you have well water, Sorrell suggests the plastic model because it is less susceptible to damage from untreated water. Shutoff valves in older plumbing systems can be corroded, especially when connections are threaded instead of soldered. An uncontrolled geyser under your sink is no way to get started, so if the shutoff is suspect, use the main shutoff valve, located where the waterline enters the house or at the pressure tank. Before starting repairs, turn off both water-supply lines. Replacement cartridges for this Moen faucet come in brass or plastic.
Plastic is less expensive and works just as well.
Pop to the cap on the top of the faucet with a screwdriver or utility knife, then remove the single screw to free the faucet lever. You might need to work the lever back and forth gently to pull it up. Use slip-joint pliers to free the retainer nut uncovered when you removed the lever. You will cover this nut when you reassemble the faucet so don't worry about marring the finish. Use a thin-bladed screwdriver to pry out the retaining clip that holds the cartridge in place.