The button melodicas from hohner have quite a following, perhaps not on this site so much but they are very popular for their sound, shape and playability. Have a search for Hohner Student, Hohner Alto and Hohner Soprano on this site. The Hohner student is a push button that is featured on Darren’s 13 melodicas comparison video on youtube.
I love these little guys. I have a pretty decent collection of vintage melodicas that includes a couple of rare hohner models that are celebrated for their unique sound and the push button family compares well amongst the more fancied melodicas like the Piano 36 and Pro 36. I am always impressed by the sound and volume from such a little instrument. I think they are easy to play and the painted metal is a nice touch, which is superior to plastic imho.
The pushies will never be as nimble the key style melodicas for playing more complex pieces but they make up for that by being very easy to play with both hands due to their size and shape.