Walkman 3.0

Walkman 3.0 is for db3510, and db2000.

(w960 is db2000)

Hi,
I have a W810i, and I would like to buy a HPM-90 headset, but I heard that it doesn't work perfectly in Walkman 2.0
Is that true?
And WHAT EXACTLY doesn't work in it?
Thanks!