We have two separate sinks, but it wouldn't be a deal breaker. As long as it's not a tiny little bathroom it would be ok. As it is, the wife has her stuff split between the master bath and the the downstairs bathroom. On the other hand, we have an open floorplan which includes an archway between the bedroom and master bath - no door (separate toilet room with a door). Looks nice and gives the area a nice feel, but makes it impossible for someone to get ready for work while the other is still sleeping. Hence the reason the wife has half her stuff (lots of duplicate items) in the downstairs bathroom. For my next house a lack of door between bedroom and bath would be a deal breaker.
Before you suggest it, we have considered putting a door in but given the layout it would pretty much have to be a pocket door. Not willing to deal with putting in a pocket door right now.