Saw some tips on buying from BCM over on the Lightfighter forums. Where, by the way, that brand is almost revered....
If you buy the upper separately from the lower, you pay the 10% federal excise tax only on the lower. That is because the upper, by itself, is not a firearm. And that will cost you less than the extra shipping charge for placing 2 orders, or so they say on that forum.
And BCM sells lowers with blemishes, which are reputed to be significantly cheaper. A long list of posters told how they could not reliably even find the blemishes, or if they did find them, the blemishes didn't matter. One guy said the color inside the mag well was not even. Big deal
Bart Noir
Whose only BCM part is the new charging handle.