mljenkins, is this new equipment? If so, I'd ask the dealer. Even if they say that it's OK they'd kind of be on the alert that you're concerned; if it should worsen (not necessarily assured, but possible if there IS some sort of defect) then they would likely be a bit more responsive (hard to dismiss something the second time around).
Seems that the general rule of thumb is that everything tends to leak down and it's really the rate that is of concern. In the case of a backhoe's stabilizers they're not typically down in the same spot for a long time during operation in which case any leak down isn't likely going to be detected (if one finds that one is "detecting" it, having to adjust during operation, THEN it starts to become/is an issue. Parked and not in use, well, not so much. I make it a habit to check the state of all attachments when going to first operate my equipment: sometimes I forget and I realize that it's MY fault.
I have a check valve on my NX5510's top link to help keep stuff like my box blade from drifting down, something that absolutely WOULD happen fairly noticeably when operating with its weight (1,200 lbs).