I too went with the St Pats TC spray ball. I also bought a 4in to 2in reducer cap from them. The spray ball will need a 1/2 HP pump that can get the 50gpm desired spec. Hose size is the key......that and I suggest you use PBW or a home-blend to add some lubrication to the spray ball.
If you circulate the PBW for a good 15min you'll clean the heck out of the fermenter. Rinse with warm water and finish with some Starsan. It's more time consuming than a basic carboy but it's still fun. It's a good time to light a cigar and work on your next recipe!
I've used Sankey kegs in the past to ferment and cleaning them is basically the same except there's no return flow....obviously.
my next challenge is to rig up a cooling system with a control valve to run multiple Brewhemuths.
This hobby never stops growing.