Are you signed up to SOR forum? I recently recommended someone the XBC and im not sure if it was you. But yes, I have 3 years experience with this bad boy. It is one of the most fun things to combine with lego, ever!
IC has never let me down, its one of easiest control environments ever made. I participate in Botball tournaments in New York every year which uses these controllers.
It takes about 1 hour to fully charge, the more hours you give it, the higher performance. Its very smart, I had cheap Hobbico 15 dollar servos and motors which the XBC treated as digital servo/motors. You can easily get position from them, set position, read voltage, control velocity, plus more. Its quite amazing for any hobby project actually. Theres a ton of C commands I dont know yet using IC, so the XBC is actually very very capable of much more.
Attach a gameboy on that biatch (any gameboy you want) and it’ll give you color camera feedback, and all the RGB/HEX readings of the camera including light points and anything else it detects. You can easily upload code to the latest XBC using a miniA-B cable which is provided for you, and of course as you know the INTERACTION tab is simply awesome. It will run any code while the XBC is connected to your computer at real time, and move servos/motors at your command without downloading the code every time.
Programming with the XBC is childs work, especially when the gameboy is attached to it (which is required btw). Hit the L/R triggers a few times and you’ll have more info at your hands. Put the robot down, go to the motor position and read the number; move the robots motors, itll give you the latest number of its position. From here you can do anything, plug the numbers into your code and your robot will repeat what you did by hand.
Its pretty awesome, please email me or PM me if you decide to buy it, ill show you around all the hidden things Ive figured out and you can show me how to use PID and backemf, which Im not the most knowledgable on. Ill post detailed pictures if you want, because that website only has 1 pic.
And also, how did you find that page of that robot that uses the XBC? To be honest, I have googled and googled and have yet to find one page of anyone who has used the XBC and documented it. If you find any more pages or can tell me what you searched to find it, please tell me! Im eager to learn more about the XBC but cant because its so tough to find others who have it. Hit me up in a private message, Ill help you out in exchange for some info on C 
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