At that scale, hiring your own quality support and running open systems is a drop in the bucket.
If you want the full IBM/Redhat experience, then you can even afford to hire 5+ layers of middle management and PMs between you and your engineers.
"support" doesn't mean reading man pages, it means diagnosing and fixing some intermittent bug in Intel's 10G NIC driver.
At that scale, hiring your own quality support and running open systems is a drop in the bucket.
If you want the full IBM/Redhat experience, then you can even afford to hire 5+ layers of middle management and PMs between you and your engineers.