UPDATED REVIEW - October 7, 2014 - CASIO AP220 & AP420 pianos are DISCONTINUED but still may be available at a couple of on-line dealers - The Casio AP220 & AP420 were good pianos in their day, but the newer "50" series is far better and vastly upgraded in terms of realistic piano key action, piano sound, and pedaling sustain response. If given the option of buying the AP220 or AP420 for a reduced discontinued price or buying the new Casio AP250 or PX750 piano for a similar price or the PX850 for a slightly higher price, I would recommend you go with the newer models. Casio America also has the upgraded Privia PX850 digital piano over the AP420 in terms of much better piano key action movement, the keys themselves the quality, response & expression of piano sound with much improved acoustic piano sound realism, more realistic pedaling sound reproduction, and upgraded internal speaker systems.
AP420 & AP220 now discontinued - PREVIOUS REVIEW from 2012 - Casio is a famous electronics company from Tokyo, Japan using the latest in robotic and digital manufacturing technology for their digital pianos and other products. I know this because I had the privilege some years ago to visit the Casio piano factory in Osaka, Japan and was very impressed with what I saw. Casio has been making their digital piano line for 30 years which is a very long time in the world of digital piano technology, so they know what they're doing. Also, as just about everyone knows, Casio is well known for good quality, low priced calculators, cameras, watches, keyboards, and many other electronic devices. I have personally owned Casio products through the years and they have been reliable and useful.
Casio PX850 review
Casio AP250 review
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