As much as it pains me to say it. Go with an AEG. They are more robust when it comes to temperature, and cost, and efficiency. Now, that being said, if you are in airsoft for realism, than I personally say go with a GBBR. Why? It functions identically to the real steel version.
I just really hate the electric whine of an AEG. Yet, I love my P90 (AEG)....
I also love my full metal KJW M4, but to give you an idea of the price...
Full metal KJW M4
ACOG Red/ green sight
bipod fore grip
barrel/ bolt upgrades (highly recommended)
5 mags total (30rnd each)
The gun you have right now should be fine for claybank. But, as said earlier, make sure you have more than 1 battery because it is a 2 day milsim.