If you like, go for HTC P3400i, come to XDA Forum, use one of my ROMS and you will be more than happy with the device.
1. Music quality, at least in headphones, with AudioBooster on is quiet good. Trebles are a bit less clear but bass is quiet tub-thumping
My personal opinion though.
2. Camera, average: takes nice pics in daylight, pathetic at night, though night mode works sometimes.
3. Video : 240x320 xvid or divx coded movies works fine using TCPMP. But nothing to boast about as the processor is a bit slow.
4. File Management, Album Art Searching etc etc : No worries, Slide2Play or Audio Manager will definitely catch your fancy, i am sure.
5. Battery Performance : Average to Good, on Windows Mobile 6.1 ROMs you will get around 2.5 days, on 6.5 ROMs you'll get 3 days or more. I am assuming 1.5-2 hours of calling and 1 hour of music listening and touch screen fondling in it
All in all, P3400i is a great phone if you are ready to give up the traditional way of using phones and accept that its not a phone, its a PDA. Windows Mobile Standard devices like the HTC Vox will give you more of a traditional phone like experience.
Plus, with the default OS that comes with the device, you wont be able to do much. It is pathetically under optimized to work on its hardware and thats why people get a bad impression from it.
Flashing a custom made ROM like mine will void your warranty although in 99% cases that i have seen, HTC service center guys are aware of these things and they don't even ask a single question to get the device serviced if something goes wrong with it.
You will have to study some information first in order to perform an upgrade, i have written a step by step guide for that on XDA Forums, so that wont be tough.
If you make decision to buy an P3400i, you are welcome on the Gene section of XDA to make it better, thats all i can say