I have the HD-HP3, 20gb jukebox by Archos, I've had it for going on 3 years now, it has NEVER been turned off, it stays connected to my machine 99% of the time and when it isn't, it's stiill left on. I have not had a battery problem, a performance problem or any damage to it ever. It's performed perfectly and shows no signs of ever failing to. I think it's about a bazillion times better than the iPod. It seems designed to withstand a nuclear attack, I've dropped it, sat on it, thrown it across the room to people, spilled soda on it, nothing will damage it. I'd recommend it highly. On the other hand, if you look at an iPod the wrong way it breaks. The battery has a built in self destruct sequence, it's enormously expensive compared to the Archos, but, it has that "I'm so cool looking" factor so I have one of them too.
Can't say anything about your Archos but, I paid like $200 for mine, that was years ago, so, I think you got taken for a ride or something.