Now this is something that I did not come up with myself, like most people, we learned it from someone else. After reading it, here on Faeit 212 in the comment section, I went and did some reading and thinking on the subject.
So take your Quad-Guns, add in an exarch from a Fire Dragon Squad and you get some amazing results. Here is why.
Fire Dragon Exarch
Crack Shot: The enemy may not take cover saves against shots from the exarch
Tank Hunters: You get to re-roll failed armour penetration rolls against vehicles.
What else do you need. Hit flyers on a 2+ with 4 S7 AP4 twin-linked shots? yes please. Can't take cover saves against it, with Tank Hunter re-rolls on the penetration roll. wow.
Of course any smart player had best be doing some serious shooting to take down that Quad-Gun if you are going to be facing this with flyers you want to keep alive. However, for eldar, right now its a great thing to be using.
A squad of 5 Dragons including Exarch with the add on abilities listed above is 120pts.
A big thanks to Black_Rose for the comment.