Submarines.

[stormbringer3]

Has anyone researched and used them? If so, what did you think of them?
Thanks for any opinions.

[Platoonist]

Once as the Confederacy. Although the sub had a certain nuisance value, I wasn't too impressed. It winged a few Union gunboats and usually got slammed in return. As the Union I've never bothered with them.

[YueJin]

Used them a couple of times as the CSA. They can be quite frustrating for the Union to deal with if you position them a couple of hexes in front of your ironclad/monitor fleet. Quite often a Union ironclad will blunder into it and take 3-4 damage and lose its AP setting it up for an easy kill next turn. It's worth teching and building them at some point to run a pair out of Charleston or Mobile since it will only cost around a division worth of MPP and by 1963 most of the core research should be done anyway.