Good info from everyone. I'd like to offer up my experiences, just so you can see a bit of a different perspective...
1. My G4 (and my old 7+ prior) never require(d) a 'settle in' period. I have seen lots of folks say it requires this break-in period, but that has not been my experience. It just works from the get-go, same as it ever does.
2. I use ONLY the outside of my bicep (right about the line of a t-shirt sleeve), and I go back and forth between arms with no issues whatsoever (no issues rolling over on it at night, or what have you).
3. I am currently out on short term disability due to dual back surgeries I had last month (fusion stuff), and I have now taken Tylenol, Vicodin and Percocet, all three of which contain acetaminophen. I have seen ZERO erratic behavior on my G4 (OTOH, my 7+ was all over the place when I took a Tylenol). Dexcom told me they have been working on this and were real glad to hear of my anecdotal success with acetaminophen products. She also told me that other folks may or may not have success with these meds -- right now it may be a bit hit and miss, until they are ready to say their system is 100% unaffected by acetaminophen.
4. As ScottD says, the Dexcom is following its own algorithm, thus it may or may not be exactly the same as your glucose meter. Just this morning my Dex said '141' and was asking for a calbration. My glucose meter read '139'. Damn close. Good enough for government work, as they say.
4b. As an addendum to #4, above, have you ever done repeated glucose readings with your meter, one right after the other, just to see if it's spot on? I have, and in my experience the multiple readings are NEVER exactly the same. Sometimes they can even be wildly divergent! Point being -- even meters can be off,
5. I dose off my Dexcom readings, though Dexcom says you should test before doing so (this is what I consider a CYA move on their part). But, they also say you can only use it when it is placed on your abdomen (because that was the only place the FDA had them test it, so another CYA move on their part).
I hope your experience turns positive soon. Sounds like it may be angling in that direction already.
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