Advantage combo unit: Automatic switching from CHARGE (Shore/generator present) PassThrough mode to INVERTER mode (Like a UPS, in fact, it makes a very good UPS)
Advantage separate units (And finally I have learned to spell Separate, thank you speil clunk). If the inverter has issues,,, for example if it looses it's mine (Mine said "Prosine Memory Error" when that happened) you still have a converter and you can still go camping.
Advantage BOTH (combo unit AND independent converter) This is the set up I have, When I had the aftermarket inverter/converter put in I choose to keep the Factory Converter (progressive Dynamics Intella-power 9180 with wizard).
Both my Prosine's converter and the Intella-power with wizard get top ratings, Finding a better one would be dang hard, if not impossible (Been looking a long time have yet to succeed) For assorted reasons I like the Intella-power SLIGHTLY better than the Prosine but those are PERSONAL reasons, as a trained electronics techniciian I would rate them (And several others) equal for most all users.
But if for any reason the Intella-power fails (It is a plug in model and has "Failed" a few times when I snagged the cord and pulled the plug) and I usually figure it out at 3AM, Turning on the Prosine's converter module does not require going outside.
The idea is: I have a back up.
Another advantage of dual converters... The 9180 can power the house, including the Kenwood TS-2000, (A 100 watt ham Transciver) with power to spare, the TS-2000 does not even know when it is running off the 9180 without batteries connected.
The Prosine is connected direct to the batteries without BEFORE the disconnect (it has it's own disconnect system).
Thus, if I need, for any reason, like a full equalization (Which in theory I should never need) to separate the batteries from the house and push 'em up to an excessively high voltage.. I can do it. And not loose any house systems while doing it. since I have a converter/charger hooked direct to the batteries and a 2nd converter/power-spply/charger hooked to the house side of the switch.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times