I don't run optics - BUIS all the way for airsoft.
The PEQ15 is there because my hand covers the entire rail space when using the AFG2 with the Magpul type grip which I use.
Here is a GREAT tip which a lot of airsofters ignore:
Build your gun around you, not you around the gun!
Start by shooting the weapon the way you want, and the way that gives you the best performance.
Then, add only the necessary accessories. Put them in places that don't compromise your shooting position.
For example:
You should read Kyle Defoor's blog:
http://www.kyledefoor.com/2010/07/bu...round-gun.html
edit: the paint job was done with laundry bag with holes in it.
Simply place the laundry bag over top the rifle/weapon you wish to paint (make sure the bag is tight against the weapon to get the best result).
Spray over-top the bag and then lift it off the weapon - you will get an awesome snake skin pattern you see.
I highly suggest you practice this technique before applying it your weapon. Test on a round tube or something with a shape to it.
Hope that helps