I would have to say the Stag Arms would be your best bet. Stag Arms is Echo 1 but with trademarks. Internaly and externaly Echo 1 is better IMO. I own a Echo 1 M16A4 and its just awsome I don''t have a complaint about it, its never failed me in battle and is always accurate. I woulden't get the one with the PEQ box I don''t like them and PEQ batterys cost more than a normal 8.4v small type. Also theres been some problems with the JG M4 S-System battery and it may require some modding to get a good fit. Echo 1 all the way!!!!
PM me with any questions you have.