Build your own Daniel Defense Rifle

Daniel Defense has a web based builder for their uppers/rifles, supposedly in advance of ordering DDM4 rifles on December 26. Kinda fun to play with. I did find out their 6.8 barrels will be 1-11" twist, at least on the 18" length. Also, the builder doesn't like the 300 Blackout, it wouldn't let me add a handguard.