Saniflo Toilets have a pump on them in a tank which pumps the sewage out of the tank once full and then sends it up a pipe and out to your sewer system or septic tank.
So no you do not need to manually empty the Saniflo Toilet unless something goes wrong with it.
When you use a Saniflo Toilet the waste goes into the tank where it is then pulverized by a macerator and then the waste gets sent through the drain pipe out to your septic tank or your sewer system.
So no you do not need to empty the Saniflo Toilet manually.