There is a reason the rafts were invented, and is to save your life. All liferafts are suposed to comply legislations that apply everywere. Some are
USA certified, others are CE certified, but there are common caracteristics:
-Must flotate even if not activated
-Must carry several survival items, such as water,
food, knive, mirror, and so on.
-Must protect you from wheater.
-Must have an auto
inflatable device.
And several others.
So, the answer is yes, it is positively buoyant.
I have seen rafts in every strange location in a boat, and it is not good at all. Must be in such a position that is easily accesible and really fast to deploy. Inverted or not. If you do not abide by this, you are endangering your life and your crew´s life.
some other boats have the raft attached with some strange stuff to make sure don´t get
lost at sea. Should have a proper system that let you release it fast and in an instinctive way, not need to know how to untie certain
knot.
Some other rafts are expired. This can be very worriesome, since the raft must be propely certified that the cilinder is going to inflate it, that provisions are not expired, that the rubber is still in parameters, that the activation mechanism is working, etc.
Also, you can get in trouble in the middle of the Altantic or just a mile from the marina. Keep your raft in the correct position always, no matter what.
And lastly:
Dinghy is not for survival. Can´t protect you from rough seas, nor cold and sun, rarely there are provisions in it, nor water. They are not highly visible from distance, nor have
radar reflectors. Gasoline in that boat can only take you a small distance.
I think we all need to be properly trained for such situations. There are formal instruction on how to respond to the emergencys, how to deploy the raft, how to use irs items, survival techniques, first aids, etc.
The better trained, the less time you spent thinking what to do in a hurry situation.
Hope I helped you.