Piano Accordions are making a quiet comeback. They are more controllable than any other keyboard, due to the bellows! You get volume & rhythm control from the left shoulder. Even a small one produces a good sound (if in tune) - bigger ones allow a larger range of sounds due to the extra switchable banks of reeds.

Many 'commercial' - i.e. professional, groups in Country, and even 'Pop' music have one - often tucked away in a dark corner, but they are increasingly being put on the front of the stage in the lights. I do notice however, that many groups only want them for the keyboard, as it is obvious that the Stradella bass is not being played. They also appear often in TV ads soundtracks.