I have never used a two handed rod so I have no personal experience. However I do know that there are some anglers who have been using two handed rod for fishing the surfzone where really long casts may be desired. Most Pacific surfzone fishing is done within 60ft or so of the beach but there are some areas where a longer cast may be necessary.

People I know who have tried them on the open ocean have found the longer rod more tiring to handle in an ocean swell.

I have been considering getting a two handed rod to try when fishing our local bays from shore since the extra distance possible might allow me to reach deeper water.

I know of a small number of anglers who have been using two handed rods on inland waters for making long presentations with topwater flies for stripers and largemouth bass, thus developing an inland still water application.