Ring Gear damage

Guys,
How often would you have to replace the flywheels ring gear. Ive been around cars my entire life and never needed to or heard of anyone doing so. The reason I ask is Im thinking of a new steel flywheel with integral ring gear. Much cheaper than a seperate ring gear flywheel. Im also assuming in the unlikely event of damaging one it could be machined off and replaced with a replacement.
any thoughts?
Justin P
How often would you have to replace the flywheels ring gear. Ive been around cars my entire life and never needed to or heard of anyone doing so. The reason I ask is Im thinking of a new steel flywheel with integral ring gear. Much cheaper than a seperate ring gear flywheel. Im also assuming in the unlikely event of damaging one it could be machined off and replaced with a replacement.
any thoughts?
Justin P