I got one here. The only real issue I've had is that it doesn't work as well as it could with the first type of sound board like was used in Solar Ride; It took some parameter tuning to get the tunes to sound remotely right. It's generally better to use the "sound file" functionality. I would also indicate that it isn't an instant boot process; I'd recommend just using a Pi3 on it just to reduce the boot time. It can use ROM files like you'd use with MAME/Visual Pinball, so it's exactly the original rules, complete with the limited settings. You can access the original diagnostics/memory menu, but you can also, holding the button longer, access a more advanced diagnostics screen accessible via ad-hoc wifi, which means you can test individual lights, switches and coils via a tablet interface, which has been really handy; I did pop bumper adjustments by using the diagnostics to engage the game-over coil so that I could fire the pops without entering the original test mode, and then disengage it again to adjust the switches again.
The real shining feature of the kit over the other replacements is the ability to configure rules with Mission Pinball Framework, although I have had issues with a form of "lag", where it would get gradually slower in responding to switch hits. It doesn't affect single player games currently, but it can affect multiplayer games, and it can be measured in seconds at the end of the game. It's also a "from scratch" sort of deal, I think I'm the first one who got a "flips and plays" config more or less finished, and I do believe that Ralf is now including it with the main distribution as an example.