Yeah, I appreciate that everyone will have differing opinions on them, Ours have just been no end of grief since we got them, Nottingham's 1 way system for example is still out of date now 8 years after they changed it.
The emails I got were last year, just constant 3 or 4 a day with vouchers that were unredeemable against anything other than a new device, I tried speaking to CS about it and opened a ticket and they suggested I un tick the "receive emails from us" option in the acc settings, the thing was it had never been ticked in the first place and yet they still kept emailing me. In the end I had to threaten them with reporting them to the information commissionaire for repeated unsolicited emails and their response to that was to simply delete my entire account with them rendering the whole device useless ( i can no longer update it due to it telling me the device has already been registered to a different acc ).
Have spoken to CS again about it and they wont release the device and tell me to log in to my acc to do it, since I no longer have an acc as they deleted it I'm trapped in a loop. Its no bad thing though as, like I say the thing was next to useless anyway, from turning it on you would often reach your destination before it even found a sat and would just sit there "searching".
Parents have the same model as I do and theirs did exactly the same ( I say did as they bought a garmin when in the USA ). Reading on the net it seems there was borked update some time ago that caused it, but like I said I cant do anything with it, it was a 920 series as well and cost about £300 at the time, its a paper weight now lol, Just unlucky I guess.