RE: Spectrum DX7 vs Futaba 7c (2.4 fasst)???
All the 2.4 GHz receivers will have low voltage reboot issues as they are all little computers.
The problem is that our 72 MHz receivers are pretty dumb so they are less voltage sensitive. We may have been having problems all along but never felt it.
You have seen more about this on Spektrum because of the large installed base and because the receivers take longer to reboot, 3-4 seconds is what I have heard. The XPS reboot very quickly. There are so few Futabas out there that we may not be hearing about the problems.
If you properly size your receiver battery so you don't get voltage sag below 4 volts you should have no problems. If you have a BEC that is feeding your servos, make sure you are not overloading it.
Even with XPS or Futaba, assuming they can reboot faster, you still don't want to be in this situation. Many users are now going to 5 cell larger capacity receiver packs to insure this does not happen.
Just new stuff to watch based on new technology.