G&G T4-18 vs. KingArms VLTOR M4

My friend is looking into getting a new AEG. His two choices come down to the King Arms VLTOR M4 and the G&G T4-18. My question is which weapon would you recommend it based on durability. The T4-18 by G&G is a blowback AEG, running at 400fps with a significant rate of fire, somewhere in the 900+RPM, while the KingArms has a very respectable gearbox running at a relatively safe 300FPS. Here is my own opinion on the matter, feel free to correct me where I may be wrong and inform me on what alternatives are possible to my view:

Pros for KingArms:

http://redwolfairsoft.com/redwolf/airsoft/ProductDetail?prodID=26342

Superior External Build
Superior Reliability
Looks BA

Cons for KingArms:
Low FPS
Price very high

Pros for G&G:

http://www.airsoftgi.com/product_info.php?cPath=139_24_107&products_id=4434

High ROF
High FPS
Excellent Performer right out of the box
Decent external build
Lower price than KingArms

Cons for the G&G:
Blowback function could lead to reliability issues
High FPS and ROF could also lead to long term reliability problems

Thoughts/comments? Thanks in advance.

Of those two the G&G imo would serve him better,

BUT if I had that kinda money to invest i would get this http://shop.ehobbyasia.com/aeg/magpul/index.html

look at the specs and it is a solid gun, internally and externally

The G&G "Top Tech" blowback does not reduce reliability.
Baisically, the TT design is nothing like the old "hook the bolt to the piston" method that a lot of VFC's and other guns use. Instead, it's got something like a direct impingement gas system where some of the air coming out of the cylinder pushes back the bolt. Therefore, you maybe lose 10 or so FPS, but increase reliability, and the bolt goes back AFTER the shot like a real firearm.