Addendum to previous statements:
I did some more research on ignition coils. Wikipedia states older coils are filled with an oil or similar liquid. These are the coils I'm most familiar with and are most likely to leak. (Any coil that is leaking, even if still working, can be considered damaged and should be replaced.)
Wikipedia further stated that modern coils are filled with a solid epoxy-like substance instead of a liquid. Some epoxies can melt or disintegrate if exposed to elevated temperatures and could result in a modern coil leaking. Regardless of whether the coil is leaking or not, prolonged exposure to elevated temperatures could damage the coil.
All things considered, there is a valid argument for replacing a significantly older coil with a modern one of the same physical and operational type. (OEM-equivalent.) However, I see little reason to replace a working older coil, unless you're willing to spend the money to bring your motorhome up to better-than-new condition. (Even then, there's lots of other things I'd spend the money on first.)
