Brown Road, the Multimatic 200 and Millermatic 200 are different machines. Pretty sure the MultiMatic is a new model in 2013.
I bought my MultiMatic 200 for the portability. I weld in 3 locations so for me portability was important. Also wanted to have a stickwelder if I need to jam an electrode deep into rusty metal, or weld outside in the wind. I haven't used it as a stick but I will someday. Also bought the spoolgun for Aluminum but haven't even opened the package. And I also want to TIG someday, but I think The MM200 is a DC TIG, which is not great for Aluminum, but may be OK for steel. I don't know much about TIG.
Then a few months later Everlast came out with the 140E for $400, pricewise, I could have bought a 140E for each location and carry just the gas bottle around? ,,,,,or something, and have more than few hundred$ left over. Well anyway I've got the MM200 and I do like it. The 230v capability provides some headroom for thicker material or larger weldments. I recently completed wiring 230v at my garage at home, so if a project needs 230v I have to bring it home.
The Multimatic 200 doesn't give you a good way to tie up the cables (for portability).
I'd say the main pluses are light weight/portability, 115/230v operation, and the option to stick-weld. If you are OK with the cost, then you are getting a special machine, and paying for it too. It sure welds sweet! In my case I haven't needed more power as most of the stuff I build is 3/8" and less. It's kind of a hard machine to "recommend" pretty much if a guy needs one he knows the price and already knows his 'needs'.
I don't have anything to say about duty cycle, as I've never had a machine shut down, ever. I can't think of any welds longer than about 6 inches though, so maybe that's the reason. I don't weld for a living and have no reason to consider duty cycle. If it welds 6 inches, that's probably enough. My 120v Miller 135 never shutdown either. Are you having problems with the welder or the supply breaker?