Alright here goes... For mass gaining you'll want to use Dbol or Anadrol as the oral steroid... They manifest themselves quickly with mass/strenght gains which sadly are hard to keep. Winstrol, Anavar, Primobolan, and lets throw halotestin in there are good for various reasons... Winstrol is a good muscle hardner which will increase your strenght also, Anavar is also a good muscle hardner and a better strenght increaser then winni it's also easier on the liver, Primobolan tabs are going to give you the lesser effect of primobolan depot which is a good safe steroid which can be used in mass/cutting cycles, Halotestin is a pure strenght steroid... Aggression is very real side effect of this steroid along with its abilities to be very liver toxic... Pound for Pound I'd like to say Anavar is the best for keepable gains and others might disagree with me... But we are talking keepable gains here... not the most gains which in turn will be lost. The pro's and con's of anavar see anavar with much more pro's and far less cons compared to the rest with the exception of primobolan... but again primo tabs are a very weak compound.