I would guess they are coming from the same source. CDNN sells for $299 plus shipping. Buds sells for $359 shipped.
I bought one from CDNN and am satisfied with it. I bought a 4586 from Buds and was happy with that purchase. I don't think either will hand pick for you.
The 5906's from CDNN are in a lot better shape than the ones from Bud's. I looked at the ones from Bud's in there retail store, and they are rough and $60 more. I ordered one from CDNN and it looks Very Good, I'm happ with it.
Got one from CDNN about 6 mos ago. Very nice condition except for the grips, which showed some wear. With new grips for under $20, the gun looks almost new.