I have dealt with them once before.
I had a DD 1.5 rear sight that had the aperture installed backwards.
They sent me a UPS tag and had it back in about a week.
I had to email them several times to get it though. They said the girl that normally did it was out, they actually sent me 2 UPS tags.
I would let DD take care of it, they should stand behind their work.
I am no longer participating in gun forums.