Well I have a 2005 Damon Intruder 377W and you described it.
Now this varies from RV to RV but here is how mine is set up
Front "half bath" toilet is a common Sea-Land Gravity Type Standard RV toilet
Rear "main Bath" has a nice Tetfored macerator unit that pumps it up to the black tank amid-ships
Front lav, and Kitchen have a gray tank, which for dumping is the standard RV Gray/Black setup like single bath RVs.. Rear Lavs and shower have a 2nd Gray tank, technically a "Wash" tank since the kitchen sink is not included, that I dump differently.
Other setups... Basically reverse the Gravity/Macerator toilets.. Some combine the gray tanks, some do not. But all in all I liked it.
In fact.. As a Single RVer, I do not need two toilets, but when my wife was alive more than once the phrase "2 holes no waiting" was a .... Well, let's just say it was great.. Cause with only one hole "We'd have had a situation".