Pretty good

It is fun to work with that app. Esp. the magic wand is really good. Cutting out even complicated objects (like hairs, plush animals, helicopters) is quite easy as soon one discovers the tools in details.

One helpful tool should be added: mark an area and expand it by some pixels to remove nasty "halos" or edges.
I like this app!

Trolleria about Superimpose, v4.5