Your best bet for good quality for a decent price would be to lurk around the Commerce section on this forum.
Aside from that, the G&G Combat Machine is always a solid platform, with plenty of upgradeability. (I would believe you could upgrade a CM to outperform one of their TopTech lines for cheaper than buying a TopTech)
Lancer Tacticals cheaper line are ok performance and internal parts wise, but their externals leave something to be desired in my opinion. (Their higher end replicas are of Lonex OEM, and are quite nice)
And the Elite Fore CQB/CQC line (Ares/S&T OEM/system) are decent. (For pricier Ares guns, I would prefer to stay away from their E.F.C.S.. Basic microswitches in the cheaper ones I find have less issues)
Keep away from SRC, Valken(SRC with like 2 better internal parts), and APS(A Piece of Sh!t).
JG, CYMA and A&K are alright. You get what you pay for. And my preference of the three is in order of preferred to least preferred.
All of the above brands can be found for, or less than $150 new.
But for a good deal, definitely as I stated first, check around the Commerce section and see if you can't find a gem.
