I would recommend you think about what the gun will be used for and build it to best fill that need. whether it be hunting or HD or anti Nazi or target shooting etc...Then research what parts and options are best for that application.
IF you get it together and end up not liking it then you can just change it up as many times as needed until its to your liking...it just gets real expensive real quick to do that.
IF you get it together and end up not liking it then you can just change it up as many times as needed until its to your liking...it just gets real expensive real quick to do that.