If it is cheap enough I would say go for it.
Don't pay much more £20 for one.
I bid on a AGP 3000 model one and got it for £15ish with TV-OUT.
AFAIK unless this has changed OS4 will ship with only an OS4 recompile of WARP3D in its current state.
So If you want to play Warp3D Demos & Games on your AmigaOne from day1 when OS4 is released then you'll need a Voodoo3 or Permedia 2 based Card.
I'll be putting my Voodoo3 back in A1 when OS4 drops theough the door and swapping it out when the ATI 3D driver is done.
Saying that If OS4 ships with ATI 3D drivers I'll be sticking it on ebay
As for performance I can't fault it. Got one in m A1200 as well. Fast refresh does 1280x1024 24Bit good enough for 17" TFT monitors. :-P