Trailer makers use multiple suppliers, to them the only difference between an Advent, a Dometic, a Coleman and some other A/C is which cost the least TODAY, that's what goes on the roof.
I have half an Advent Air 15000 BTU in my bedroom, it is my primary A/C and is the one that runs most every day and night, it is running as I type, it is 2 years old come August if I recall correctly, if not it's 3,, The other half of the A/C is a Carrier Air V. the Air V had a manufacturing defect and died, but alas Carrier no longer makes.. The only thing I've done to the Advent is routine cleaning.. (It is a direct replacement for the Carrier roof-top unit, you change the roof top uint and one conector on the control board is all, They sell an adapt-a-kit, consists of 4 new mounting bolts, a "Y" cable, the new Molex snap in connector (I had to teach the dealer technician how to install those,, thankfully I am an electronics technician, (Certified no less) we are kind of used to MOLEX products.. I will not tell you what many of us think of them though... Do not wish to melt your monitor,, (There are better connectors))
Works great.
I got 1,500 more BTU's and it draws the same 13.5 amps as the 13,500 Carrier it replaced.