I haven't seen the hot box, White bros has been out of business a while now so I don't have a good web page to look it up. But my guess is it's based on the same Dobeck controller than most of the rest of the tuners out there are. Not sure which generation of Dobeck it would be though.
They work great with the big3 setups. Not enough adjustability for big HP machines but perfect for the everyday rider. Oh and is that the aluminum pro2 white bros. full system exaust? If so you're gonna love it haha I had one and holy hell that thing was loud. Everybody hated me Wasn't to bad with the quiet core in it though and gave me some good HP/TQ gains. Only problem is like MD said WB is outa business so you wont be able to get parts for it. Vance and hines bought them out and then discontinued the line.