Re: IOR 2-12x36 MP8 or CQB reticle???
I would not get the 2-12, I didn't like it.
If it's going to be a heavy barrel rifle that is a range toy I'd save up and get the 3-18x50 FFP if you want to go IOR. Otherwise I'd get the 2.5-10 IOR FFP.
Other scopes to look at would be the USO 10X, Super Sniper HD 10X, Razor HD 5-20, and of course Nightforce 2.5-10, 3-15 and 5.5-22.
No matter which one you buy you will not be "going wrong". Best of luck to you.