I'm curious to hear what you find out regarding the spinning threshold for your unit, compared to mine.
I hope you are not wrong about the time issue. I do observe that the time presented in the LiveData screen continues updating even if it is refreshed in between two requests to Wunderground. I can be sure of it being in between using network packet sniffing. So at the very least this implies some kind of software based clock, perhaps hardware?
Fine Offset has informed me that they are investigating the option of adding an NTP client. If the clock is software only, its drift rate could then determine how often this client code should be activated to maintain a certain quality standard of the unit's clock. Assuming that no sub-second accuracy is needed, this requirement might not be too onerous.
Assuming this time issue gets fixed, hardware clock or software + NTP, and assuming your "spinning lift-off" issue is not representative in general, I would say that for its price the Ambient solution remains quite attractive. I agree the Davis solutions are overall better, and in some respects significantly better, but not everybody can afford the price. I've been reading some reports of failing sensors an replacement cost. Often times the replacement cost is more than a completely new Ambient unit.
Of course, all of this does not say anything about one's requirements as far as calibration, sensor separation, reproducibility etc. Davis clearly has the edge there, but not everyone may need that.