It also depends on if you are planning on keeping the gun as it looks or if you want to modify its external aesthetics.
Making sure you get a proper warranty is also very important, you do not get that with used guns.
The tinted receivers are darker on the ICS than the G&G. The ICS dark receivers are much more solid and do not break as easily.
ICS has more guns to choose from including their own models like the CXP concept and other modified models.
Feel free to come and feel them out at our store: www.SurplusIG.com