Been using two handers in the salt since the early 90's ........ just not spey rods.
The requirements are vastly different from a two hander used in the salt and a spey rod used in a river. Both are excellent tools when used as intended just neither is the best choice for doing the other.
In the salt you want long, fast, and powerful in the surf.
Fact is Rocket the first spey rod I ever saw was a picture in a 1960's Joe Brook's book of an Argentine spey angler. 18' bamboo or greenheart rod as my memory recalls.