I am sure there will b people who don't agree but for the money (£120-£140) a g&g cm is, imho, the best m4. If u are getting back into the swing of things it will give u a great gun straight out of the box but also a very easy fun to work on and upgrade.
I also know it's not everyone's cup of tea but I really like the g&g fire hawk. Great if u are playing a lot of cqb.
Am sure the usual g&g bashing will continue however from my experiences and that of many others it is unfounded.