Depends. If you want the best of parts, and a rifle that you want to your exact liking, it can cost significantly more than just buying a stock rifle. The advantages to building from scratch are you get it how you like, without spending "more" than you need to (for instance, buy a stock rifle, then put in/on what you want). The disadvantages are the gun will not have the quality control that you might get from CA or Marui. Also, it does take some patience, becuase they might not have what you want in stock, and it takes time to get it built properly, and have it work properly.