You can use the 3" standoff. I have that for my DA, but ended up using my 2.5". Either way, you still HAVE to use the pull pull, if you go with the DA. I had a DA on hand, and so that's what I used. If I were to start from scratch, then I'd probably use the Evo58. I doubt I'll feel the difference in wingloading that much. But I sure will feel it on the pullout (not to say that pullout with DA is bad).
I used 1" Dubro arms on the ailerons (cheapest method), and 1.25" on the elevators (you can probably use 1.5" also, but 1.25" is what my LHS has). I used a tiller arm because it supposedly makes your BB on the servo last longer.