I've been using a black box ever since I had my old classic '85. Quite a few years. There's lots of conjecture out there regarding the efficacy of that little add-on, but my take is, yep, it works. If the fishing is really good it doesn't make any difference whether you've got the box or not. By the same token it doesn't make much difference whether you're dragging a high tech lure, herring or a jim dandy bottle opener. But when the fish aren't trying to jump in the boat the black box will do it's job. I refer to it as my fish magnet. Dick Poole's treatise on the subject is pretty good and I agree with it. Works for me........plus it is really nice to find another widget to play with on the boat.
Yep, I've got one on my new CD, 3rd Byte.
The original Scotty black box was pretty spendy, I believe considerably north of two bills, but Cabelas has the equivilent for 99.99. The "Cabela type" were available at Outdoor Emporiums booth at the SBS last year for 79.99. As I understand it, the guy that is furnishing Scottys black box for them is now making the black box for Cabelas and other outlets. Basically the same innards in a different housing (for obvious reasons).
Good luck & Happy New Year!