Intel GPUs != solid OpenGL drivers. I do a lot of work in OpenGL and I curse Intel almost daily for the multitude of bugs in their OpenGL implementations.
The GPUs' only saving grace is their ubiquity so at least I get a bug report quite quickly when a work-around is required.
Are you specifically talking about the Linux drivers for Intel GPUs? Their OpenGL implementation is based on the open-source Mesa project, which, while not perfect, has been worked on steadily for over a decade, and has been pretty solid in my experience.
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
