Carrier specific charging accessories required???

[snakey5138999]

Hey guys, about to get my new tp2 that i won off ebay for $300, to trade for my instinct. When i bought my instinct, they were very forceful of saying only use sprint accessories (Batteries, Chargers, Docks) to use with your phone. If not, it would ruin your phone, as they've seen it before and not be covered if any damage occurred. They claimed they would know that an aftermarket accessory was used with the phone that caused the damage.

Has anyone had any problem using ebay accessories as to the ones ive mentioned? I bought a $5 battery for one of my old nextels off ebay and it worked great! Held a charge and saved me $30 over buying new from sprint. Seen the same thing for tp2 batteries for like $8 compared to like $40 from sprint. Plus i dont feel like spending $35 on a car charger when i can get one on ebay for like $3...

Any opinions from experience??? Thanks