Aftermarket Equipment

I'd say a lot of cheap non-oem accessories can potentially be bad for your phone because you can't be sure what kind of quality control went in the manufacture. I'm seeing more and more accessories available on ebay that are cheaply produced overseas and those are the ones I trust the least.

I charge my phones in the car with an I-Go charger that was recommended by Radio-Shack and at home we use the OEM charger. Generally, you're okay to buy a reputable brand that's not OEM, but it should list your specific model on the packaging (I-Go is supposed to be compatible with anything). Also, make sure that it has some kind of surge protection; I'm pretty sure the I-Go has a fuse.

I'd never plug my phone into anything cheap, so you might as well buy OEM. The I-Go was $30 but I can change tips and charge my digital camera, mp3 player, and other devices so it was a better choice for me.

Oh, you asked about batteries? Yeah I'd never use a non-OEM battery; had a bad experience with my first phone because the guy I bought it from stuck a cheap generic battery into it so he could sell the Motorola battery on ebay.

Just because one comes from the same country as another doesn't guarantee comparable quality! If that were the case, I'd be buying all generic items at the grocery store to save big $$$...

My parents used to always say, "When you buy cheap stuff you get cheap stuff."

Good point.