Well, I bet just about everyone uses it with other supplements. It's wierd they don't specify what would be a bad combo. Vitamins?
I'm not sure about the 12 week thing. Some people take natural test boosters year round. Some of them say to cycle on the bottle, and some don't.
Personally, I like to switch around between different types of test boosters. Just so the body doesn't get used to one. The thing with HCGenerate is that it has a lot of test boosting ingredients in it that are common to other products. But switching off between it and DAA might be a good plan.