Personally, before I'd drop the coin on a rifle like that I'd start talking to a 'smith about exactly what I wanted, then have the rifle built around MY needs/wants.
The components look about as good as you will find based upon personal preference. I've run McMillan stocks with no complaint at all, and am now waiting delivery on my first Manners. I've been slightly less enthused, but still had good results with H-S Precision stocks, and got one lemon (enough for me to swear them off) from Bell and Carlson.
I don't know if I'll ever run a Shilen barrel, but I've got a buddy that can put 5 shots into about a half inch at 200yds with a Shilen tube. Currently I've only got one aftermarket barrel sitting in my safe and that is a Broughton 5C. I will say though that you will probably be hard pressed to be able to tell the difference in accuracy between any of the top barrel makers, and Shilen is definitely one of them.
The action is based off of a tried and true workhorse, can't tell about the craftsmanship that is in it from pictures, but it probably isn't too shabby.
I'm also not a big fan of two-piece bases for scopes, but that is nothing more than a personal preference based on my personal belief that a one-piece base has the potential to be more sturdy.
The "Marine Sniper" looks nothing like any of the M40 models that have ever been issued in the Corps, just a personal pet peeve.
Some more of the thoughtful ideas that went into these rifles are the thicker recoil lug, 8-40 screws, and welded bolt handle. Might make the rifle a bit more prone to survival in the hands of someone who beats on their toys a bit while they are out in the field (optics are exempt for the last sentence).
Once again I run into the "Marine Sniper" not being a Marine sniper rifle. Besides, how many people who buy that rifle are going to use it for sniping anyways. If you want, look up some of the bigger custom stick makers on the tactical side of the custom rifle business (i.e. GA Precision...etc, the list goes on and on) and ask them to make you an M40A1/A3/A5. A lot of guys will build you one to spec of what is used out in the field, hell some of those guys used to work as 2112s and actually built sniper rifles while in the Corps. Price will be about the same as an Ed Brown.
Hope this helps, another long topic that needs a couple of pages just to itself.
Of course all this is just my .02, YMMV.