Sadly the PGI compilers are (at least in my experience with codes I use) buggy, slow, and difficult to use. Why pay when I can get comparable performance using GNU compilers?
People using FORTRAN have this weird tendency of not changing much with the times. Their code bases go back decades, and PGI compilers are something they continue using.
My experience with PGI is that the engineers liked them because they had a FORTRAN to CUDA compiler, so they didn't have to rewrite their code. They were pretty good about answering bug reports, with the number of times I had to install new compilers on the compute systems.
