ORIGINAL: Julez
Not necessarily.
My TX lost its GUID after I switched it on exactly the way I did hundreds of times before during the last 6 months.
Having spent *many* hours designing and building microcontroller-based systems I'd be willing to bet that your system didn't lose its memory on power-up but during the previous power-down.
As I've posted elsewhere, the odds are that you switched it off during the very narrow window when some EEPROM was being updated - this is something that many people overlook when getting familiar with this technology but I'd have expected Futaba to know better.
The fix may be simple (a couple of resistors and a few lines of code) or it may be more complex (requiring a separate A/D converter to be grafted on if the main processor doesn't have a spare ADC channel) - but either way it's almost certainly going to be a "return to factory" job I'm afraid.
If Futaba simply say "it's fine, just don't play with the off-on switch" then (IMHO) they'll be as bad as Hitec who said "yes, the Spectra module is a loose fit in those Optic 6's and it does cause planes to crash -- so just wrap some electrical tape around it, that'll be fine" (and it wasn't). A proper recall/fix would be extremely expensive -- it's just a case of how much Futaba is prepared to wear in order to protect its reputation as a brand.
I believe, based on what we've seen and on Futaba's own comments in respect to use of the off/on switch, that there is a definite *DESIGN FLAW* in these sets. It's not a matter of "if" your system looses its GUID -- it's a matter of *WHEN*. Given sufficient power cycles, eventually one will interrupt an EEPROM write and then you're toast.
Hitec said the AAAA fault (a similar situation) with their OPTIC 6 was "very rare" -- but that's only because the chances of hitting the EEPROM write window were small. However, all of the Optic 6s I saw with the original firmware did it eventually - buy enough tickets over a long enough period and you'll eventually win the lottery -- it's all about odds.
Futaba may opt to bet that the window is so small that the numbers affected (and planes possibly lost) won't be worth the recall -- as a consumer I don't think I'd be happy with that. One of the reasons many folks have gone to 2.4GHz is to get away from playing Russian roulette with their models -- isn't it?
All consumer electronic devices should be impervious to damage from simply using the switches provided.