I don't know much about MSVC++, but Intel's compilers are widely considered the most advanced C++ compilers, as long as you stick with Intel hardware. There was some controversy over it generating bad assembly when targeting AMD cores, but this is a non-issue for companies like Boeing and Raytheon, who will be using custom hardware anyway.
The controversy was that it generated a CPUID check for "GenuineIntel" at runtime, and fell back to extremely poorly generated code (like, 386-level, almost 286-level style) for all other CPUs, as far as I remember.
Borderline intentional sabotage against AMD, because they can obviously do better and I don't believe they are unaware of the capabilities of AMD CPUs.
(edit: And they should probably be checking for features instead of vendor IDs anyways. It's like checking for Firefox in the user-agent and sending animated GIFs instead of WebGL if you're on Chrome)
