I only update the FW via WiFi, G04/Mini4/RC, MP, all devices at same time. I make sure batteries are all fully charged so update isn't interrupted by a low battery issue (happened to me once, the update stopped when the MP battery got below 50%, so had to change batteries in the MP and lucky the update continued were it left off from). I also, found that physically putting the RC/MP close to my router helps the process moving steadily, although slow at time, I keep checking to make sure that the loading percentage keeps on moving and I have never had an issue with the update first time around. Also, I noticed that while updating, it really hogs the router bandwidth and my other computers are very very slow accessing the internet, if they work at all, so I have been shutting my other devices down while updating the FW just so I don't glitch out the update.