The mini-splits are a huge step forward if you have an older home that wasn't set up for central heat. They are quiet and efficient at cooling, and offer a dehumidify setting in addition to just fan or heat options.

But in winter you're using electricity rather than gas for heating, which isn't ideal unless you have solar power.

When the weather is changeable, you can't run a bit of heat in the one cold room and leave the A/C set to 78, all the units have to run on the exact same 'mode' although you can fine tune the temp. Apparently the main air handler that sits on the roof has to be working in one mode only. There's a little too much running around resetting each units temp morning and evening. Though you theoretically can program that with the remotes (1 for each unit).

Not excited about maintenance. Though they look sleek and simple, they sit very high on my walls, and it seems difficult to clean filters and troubleshoot. The Youtube videos I've seen involve ladders and plastic sheeting enclosures, yikes.

If she's already got ductwork set up for central heating and a/c, I'd be inclined to keep a central system going, unless the new units are crazy expensive.