SeaEra http://www.raritaneng.com/products/toilets/electric/sea_era.htmlis the best choice for a basic electric macerating toilet...if you want something a bit fancier, check out the Raritan Elegance. http://www.raritaneng.com/products/toilets/electric/marine_elegance.htm

If you have the fresh water to spare, go with the pressurized flush water version. All toilets designed to use pressurized flush water are MUCH quieter than sea water toilets because, contrary to popular belief, it's not the macerator or discharge pump that makes the noise, it's the intake pump...and toilets that use pressurized flush water don't have an intake pump, only a solenoid valve. They also use less flush water and less power.

Don't even THINK of going with an "electrified" manual toilet...e.g Raritan PHE II or Groco KE. If you want an elelctric toilet, go with one that's designed to BE any electric toilet, not a hybrid.