My daughter is on her fourth Ipod and persuaded me to buy one. Having compared it with other devices on the market, I can see what the extra price buys you.
There are two snags that I've found with the Ipod - they may be the same on other devices, I don't know.
1. Reliability. My first one died after two weeks. Apple wanted to "repair" it under warranty, but I insisted on a new one. The new one's been fine so far (6 months in).
2. Battery life. Mine is supposed to go 14 hours on a charge. I'm lucky if I get 9 hours, and 8 is more like it. However, I've got a car charger for it, and it connects to the car's sound system so I'm happy.