M-Stack is okay but the Animal Stak2 is damn good.
Gncxxx is pointless and hard to get down i would throw that out and get some more whey like Blitzkrieg said. When I'm on Mono i load with 40g and maintain with 20 but that's just me.
You could also do the M-stak and the Stak2 together
i would say if you're going to do one of the two do the stak2
4weeks on 1week off 4weeks on 1week off.
It has a lot of trib and liver supporters and anti estrogen's in it.
So you could do. 2 cans on the M-stak then 1 can of the Stak2.

And Gnc actually has great Fish Oil's IMO.