If you kept 12 pounds from a cycle, that is great! Even weak compounds usually deliver good gains on a 1st cycle. Yes, Super DMZ 2.0 is considerably stronger than H-drol, but does that mean you will gain 2X as much. Probably not. Look at an advanced user. He can use a boat-load of the strongest AAS and gain less than a 1st timer who uses a relatively weak steroid, like H-drol. I gaurantee you that many long-time steroids users are NOT keeping 12 pounds from their cycles. By the time you are advanced, you will be lucky to keep 2-3...and often guys keep none.
The point here is that answering your question is not going to tell you how much muscle you will gain on your next cycle. The more cycles you do, the harder it gets to make gains. So, I would advise that instead of worrying about how much stronger DMZ is than H-drol, that you simply focus on making the most of your cycle. Make ure you eat & train to the best of your ability and you will make the best gains YOU are capable of.
If you are looking for a number, I will say this. If you are able to keep another 12 lbs from your DMZ cycle, you will have done great. That is 24 lbs of lean muscle tissue in 2 short cycles. That is very good and something to be proud of. 24 lbs changes a physique.