I have multiple split systems in my house - works well and is reasonably efficient.

However, it looks as ugly as a gypos wife / sister from the outside of the house.

If the cost of running and maintaining a ducted system isn't an issue then ducted is very hard to beat.

However, you often find that rather than repair an old ducted system a lot of people just install split systems these days and are more than happy with the results. [ Key word being OLD ducted systems].

The reason being is that the new split systems don't cost as much to run as the older ducted systems did.