It boils down to this...very few manufacturers make a unit they warrant for fulltime use. Those that do are VERY expensive.
Most manufacturers make Recreation Vehicles (RVs). As the name suggests they are made with part time or recreational use in mind. Many of the components are not household quality, and are not expected to hold up to daily, constant use. The warranty statement that these manufacturers have, voiding the warranty for fulltime use, in most cases, is meant to protect THEM against excessive claims against that warranty because someone "abused" the unit.
That said, I've never met anyone who has had warranty claims denied because they fulltimed in their units. Us Included. The manufacturer knows, beyond a shadow of a doubt we fulltime, and they honored our warranty from day one...no question.
Stop worrying and use your unit as you like, but make sure you have realistic expectations about what the manufacturer should cover and what they should not. When you fulltime, taking it back and forth to a dealer for every little thing is "unrealistic". You need to be able to deal with small things on your own...this is where the "realistic" part comes into play. Good luck!