I think the usefulness depends on what you want to do with it.
If you are hoping to replace finger pricks, you will be disappointed: it is not as accurate and cannot be used for driving so you will still need to prick your finger.
If you want to understand trends to optimise your treatment this is ideal. The kind of thing I mean includes understanding which food raised your BG and how long it takes, how different exercises affect your BG, etc.
I always compare using a Libre for point in time BG reading is like using an iPhone to just make phone calls.
Remember when you use it that the Libre sensor in your arm takes BG readings every 15 minutes. It stores 8 hours of data on the sensor. When you "scan" the sensor, it is not doing a test; it is downloading the last 8 hours of data to your reader. This means:
- the latest reading when you scan may be up to 15 minutes out ... and this does not include the 15 minute delay reading BG from interstitial fluids
- if you scan less often than every 8 hours, you will loose data
- if you scan every 5 minutes they would not change.