hi all,
for me radeon M9000 seems to work fine, the opengl performance is very fast. I use it for two months. With the latest Dell drivers its quite good in 3D sculpt and paint tools too...
but brobably you have to install the latest driver and video Bios update.
an interesting issue: in sculpt surfaces tool its working very fine until you open an other opengl window like render view or hypershade, but after there is a very slight delay in 3D tumble and the brush track, but its much less in the newer driver, so its only a little driver issue, which hopefully will be fixed in the next driver. this is the only problem I experienced...