I recently built a virtual mame/pin combo for my kids. I used a really low end AMD APU which was around $180 with motherboard and ram. the onboard GPU can easily run any of the williams titles at 1920x1200 at 60FPS with very little input lag. I'm using a zero delay usb encoder and sanwa buttons with a Freescale developer board with accelerometer for nudging.
If this is priced around $700 they should easily be able to get enough horsepower to run pinball fx3 bally/willliams titles smoothly and with near imperceptible input lag.
However, I'm guessing they are going to use an embedded android board like an ODROID to keep the cost low and for simplicity.
What is most important is going to be the type of display that they use. If they use an IPS panel with a matte finish, it's not going to look that great with diminished contrast and colors. I ended up removing the anti-reflecting layer of the monitor before installing it in my machine. Makes a huge difference.
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