I've had the internet connection crap out while using PowerSaves quite often. With it giving me errors while trying to upload or download the save. But never had it brick or do anything odd to the game cart. Many times I used multiple codes at once without issue. Of coarse I no longer use the original USB cable. it's too damn short. I used a longer one and taped the dongle to the side of my PC tower. It's super stable and easy to use now. Can insert and pull the cartridge in/out with just one hand.
I would assume that if the internet stops working during the writing cart stage, the program would ignore that until it finishes, then would display an error. I don't think PowerSaves would be dumb enough to allow it to interrupt a write sequence if the internet connection is interrupted.
I think perhaps the bricking reports were from defective parts either the cartridge itself or the dongle. If you are afraid it might brick, just pokebank all your important stuff first. Then after a few days of using it and nothing bad happens, you're pretty much in the clear.
That is definitely reassuring! I can definitely see some of them being bricked due to defective parts and the like. And yeah, that's what I would normally do, but because the game isn't mine even though I could save her Pokémon I know she'd be upset with losing her actual save, which is why I'm taking as many precautions as I can and asking around first and all. @.@
Hopefully ORAS doesn't take too long to be supported. xD