different plug ins, eagle plug ins suck. lowrance uses a good twist lock plug, adapters are available but why bother, pay the extra bucks and get a lowrance
I too have used Eagle products for many years and have absolutely zero problems with any of them. The head unit connectors are not an issue either although a very light wipe with petroleum jelly allows them to slip together easier.
I think I'd avoid using petroleum jelly or any other petroleum based product on those connectors. Petroleum jelly is a "petroleum" derived product and will deteriorate the rubber connector.
should be able to use dielectric grease for that, no?
By golly my Eagle Magna III from gosh only knows when is still ticking along just fine.