Hey bro....first do some research and you will find a few reasons why most dont run them together. I will give you my opinion on the deal. Both of those compounds can by themselves raise "progestorone" levels in your system.....so when you combine them it can make it even higher and possibly lead to progesterone induced "gyno" or bitch tits if you will. The only way to run them together would to get some Bromocriptimine to keep in case the progesterone levels got too high. I have also though about combining those 2 compounds for the fact that i wanted the mass from the Deca and the strengh from the Tren....BUT I NEVER DID so i can not give you any first hand experiance. The Tren is great with some test prop or Test enth. and the Deca is ok for mass with a test base. As you can tell i am a big fan of Tren/Fina. If you need any more help just let me know......Good luck friend.................Trev