If it was me and my money, I would get a rifle built to my specs by a good gunsmith. Robert Vestal seems to get a lot of business from some of the top ELR shooters, I imagine there is a reason for that.
The Cadex rifles are built to function on a battle field, they are not purpose built ELR machines. If I was building a .375/.408, there are features that I would want for ELR shooting that the Cadex rifles lack.
That and I think Cadex rifles are butt ugly. They seem to spend a lot of time/machining to achieve certain aesthetics, which is no doubt built into the cost of the rifle. Call me a utilitarian, but I would prefer that money to be spent on functionality. As a Canadian, does this make me unpatriotic?
Unfortunately, in the .375/.408/.50 class of rifles, components are extremely limited compared to what we have available in smaller frame rifles. If the Cadex checks all the boxes for you, it is a decently built rifle.
*Edit - how far are you planning on shooting? Your .338 should be capable to much past a mile, especially with proper loads (some loads won't be mag length though). You can also consider rebarreling to a .30-338, which should be capable of 3,000+ yards if you really want to stretch it.