Very latest Intel is ok, older are pretty slow. AMD hardware that works with the Mesa drivers is nearly as solid as Intel, but their proprietary drivers are a disaster (kernel crashes etc). Nvidia has decent proprietary drivers for desktop stuff.
On laptops, dual graphics (Nvidia calls it "Optimus", don't know about AMD) doesn't work right so Intel and Mesa-supported integrated AMD graphics are the best choices on laptops currently. There's some light at the end of the tunnel for Nvidia: https://wiki.ubuntu.com/X/HybridGraphics
On laptops, dual graphics (Nvidia calls it "Optimus", don't know about AMD) doesn't work right so Intel and Mesa-supported integrated AMD graphics are the best choices on laptops currently. There's some light at the end of the tunnel for Nvidia: https://wiki.ubuntu.com/X/HybridGraphics