They're very good.
I've had mine since the start of August.
95% of my memory is full of music, I've about 1200 songs on there, and thats enough for me as most of the time I listen to my portable DAB, and I get easily bored with too much music and skip every other track.
The following applications I'd recommend.
m-Box Mail (Hotmail application £5.99 - Very worth it if your Hotmail is your main personal email)
eBay
WikiTap
Where
Google Earth
My Football
BBC Reader
Memory Stick
Palringo (IM Messenger)
Photobucket
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