Would say that the AOG adds their "distinctive understandings" to the person and work of the Holy Spirit, and are wrong in much of that, but again, they are NOT holding to water baptism required to save a sinner, as that would be making another gospel...
		
		
	 
Again, I don't take such an extreme view, because we could say the same thing for many believers who felt that walking the aisle and saying a prayer was necessary. They learn later, we hope, that by the time a public profession was decided on...they were already saved. 
What we won't do, though, is engage in profitable discussion if we offend our antagonist into a defensive position, which is man's wont, to forget the weightier issues in favor of a good ole argument, lol.
When we approach those with distinctive doctrines we feel are in error, it is best to let them broach the subject. When they do, this evidences one thing that is common among most of us...a desire to test our own doctrine. I think for many of us, myself included, we often have an "This is what I believe but because I am fallible I am not dogmatic" mentality when we begin understanding certain doctrines. As we test those views in discussion with others, we usually see our view either confirmed or opposed. And if we are honest in our study and faithful to the teaching God seeks to do, we will conform our view to the Biblical view. 
But, and I guarantee this, if we approach others with an offensive manner we can be sure that we will slam the doors of communication and create an atmosphere of rejection The same is true with anyone engaged in "religious" studies and views. That doesn't mean we mealy-mouth it, nor refrain from a dogmatic position on what we believe, but, there's no reason why we can't seek to fulfill what should be the ultimate goal in all of our lives, which is to see people come to the knowledge of the truth. Which means, like Paul, keeping Christ and Christ crucified the central focus. Doctrinal Distinctives such as those embraced by AoG take a back-seat to the Cross. God can use even those with erroneous doctrines and practice.
As a side note, just watched the movie "Gods and Kings." My wife became disgusted with it because it did not follow Biblical teaching, though there were some parts which did. What I think, though, and you can correct me if you think it silly, is that even with such a Hollywood production, which I feel has a motive of propaganda, because it cast God in aspersion and Moses as a tortured being who didn't have reverence for God, is that God can use this for His purposes. Atheists typically seek to use Scripture itself to vilify God. This movie will present ammunition, in the minds of the atheist, and they will consult Scripture so they can locate their proof-texts. 
And while they might not understand fully, when they consult Scripture, that it is Hollywood distorting truth, I believe God will use just such revelation, even if subconsciously, to open a door for a Bible Student to point this out. 
The most effective means of witness to atheists, and any doctrinal view, is to examine the basis for those views. And even for the Atheist, the basis is often the Word of God. When we can show them why they are in error by pointing out what Scripture actually teaches, as opposed to what they think it teaches, again, while they may not admit it to us, God can impress that upon their heart as He seeks to convict them.
I can't help but get a kick out of that. Imagine the atheist that looks into Genesis so he can have chapter and verse to blast his next Christian target...and finds it's not there.
Gotta make ya smile, does it not?
God bless.