I mainly just use ours (in basement) for additional heating in winter. Have one indoor unit right above my desk here and another in the den in another corner of the basement, blowing onto the couch there. Using them occasionally with just fan on in indoor units, mainly here at my desk where I don't have an overhead fan. The big heat pump services both the basement and the 1st floor of the house, and basement cannot be zoned out. In winter, one can freeze in the basement unless you want to run the rest at well above 70. When I was sick with CHF, I was using little direct electric heaters to keep myself warm before we put this Fujitsu system in.
It's totally noiseless, both indoor and outdoor units. I remember walking by similar units at offices in Japan. Hardly any noise. No backup heating coils in these units.
Think they can run up to around 7 indoor units. Could have gone with them instead of replacing the upstairs heat pump that we did recently, but it would have been a much more involved job, as they have to drill some holes through the brick where each indoor unit goes to run the refrigerant lines (R410a). Would be a challenge, too, where to run the lines, etc. Probably would run them around inside the eaves of the house and just drop down to each indoor unit. Would be a lot of refrigerant lines.
You DO NOT want one of these indoor units discharging right above where you mainly sit or lie when it's operating in heating mode, as it often goes for a rather long period just blowing semi-warm air before the compressor kicks in again to make it truly warm. Okay in AC or fan mode though, as that's what you want.
Ralph