getflv downloading low bandwidth - Audio/video stream recording forums

Does Getflv download/record in real time as you are watching, or can it download full definition image taking the necessary extra time as in downloading in Itunes?
My problem is some streams are terrible quality on the BW I have and may re buffer, , but can be viewed at any available resolution if downloaded taking 150 to 300% of the real playing time.
For some reason Netflix is an exception. The image looks OK with only 2.5 Mbps and never re buffers.