By what I have heard they are a rip off.
The formulas they have on the disc are formulas exactly like what we have on this site and others found on the internet.
I haven't personally used one of those CD's from ebay, but someone who did said it isn't worth anything. I can't remember who used it, this was a few years ago. I'm sure those CD's haven't gotten any better.
Yeah, it is worth nothing and is a full-on scam - a few years back, I had someone email me their instructions and, gues what, they had plagerized them from right here at Oozing Goo. Essentially, they are taking free information and reselling it. How to Make a Lava Lamp instructions at Oozing Goo.