I have one, and use my rear dump all the time, it is fully functional. My problem, is with the clip. This sausage has a clip to attach to your d ring to keep it upright (I bring it over my right shoulder and attach to my right shoulder d ring). The one time I deployed it, I couldn't keep it upright, and with it behind me, it was a pain to hold on to. I'm going to try shortening the line and see if that improves it.
CuriousMe:I have one of these actually.
I don't think there's a real risk of accidental inflation, there's a clip keeping it rolled up that you need to pull before you inflate it.
I would say it depends on how badly it's punctured, if it doesn't hold air at all, I would say probably, you won't be able to inflate it.
I haven't noticed a big difference in drag.
No, the rear dump valve is used exclusively for the sausage. I never really used my rear dump, so this wasn't a problem for me.
Peace,
Cathie