The actual stock of the National Match may indeed weigh the same as that of their standard or loaded, but the action is glass bedded into it, which does add some weight. The Super Match has a maximum dimension oversized stock that in addition to being heavier doesn't actually "feel" right to me.
I didn't even get into the whole glass bedding topic, and you are absolutely right. As the action is removed and re-installed into the stock, there is the potential for the bedding to be damaged. I don't know how likely this is to occur, or how many times it can be done before actual damage is likely to occur, which reduces the tightness of the lockup, therefore eliminating the benefit of the bedding. The general rule is to only remove the action when absolutely necessary, and preferably never.
Their loaded models come with a medium weight "national match" barrel, though I'm not sure of the actual quality of it. The website also says it includes a NM front sight, but not rear, and a national match trigger assembly (really not sure what this one means).
If I were to buy a new one today, it'd be a standard model with Walnut stock and standard GI profile barrel. I can always replace sights and all other internal components with mil-spec or upgraded parts myself.
Good luck in your decision.
