Im 6' 4" and i picked up a m14 for my frist AEG. Feels nice in the hands not overly long feeling unless i slap the silencer on it. Its 44" w/o the silencer and 53" with it. Ive held and used smaller guns like S-systems, m733s, Aks74u's and those smaller rifles and they feel really cramped for me, almost like id have to be a T-rex to use it properly. What i found was best was to pick up and handle as many diffrent types of rifle as you can befor you buy. If you think a regular M14 ill be to long for you, there is also the m14 socom that comes with a shorter barrel.
" The bitterness of poor quality lasts long after the novelty of low price is forgoten"