Re: Need a new 308 rifle...
They are both specialized pieces of equipment. The advantage of a custom build is that you can order the rifle tailored for your particular needs. Are you familiar enough with exactly what purpose you have in mind for this custom rifle, or would you be better off with a high quality factory rifle that you could re-sell quickly when you decide that your skill level warrants stepping up to a custom rifle?
Because something like an AE MK II is hard to beat for price, accuracy, and quality.