The 49005 was introduced in 1992 and I think was in the catalogue until 2001/2002 with some 800 pieces produced over this ten year time frame. The 47112 was introduced in 2000 and remained in production until 2006 or 2007. I'm sure Alex or some of the more seasoned people here can give you more exact info, in fact I remember reading a series of articles by Alex on VC calendar watches that I am certain mentioned one if not both references.
I personally find both to be significant in their own way. The 49005 was, I believe, VC's first if not one of the first perpetual chronographs introduced by VC and housed cal. 1136QP, while the 47112 was one of the first models to feature the stunning engraved moon-phase and featured the cal. 1141QP, which is currently used in the ref. 47292.