I worked in parallel with Sun Microsystems (prior acquisition) IBM and Oracle. All 3 were horrible in that regard. They all offered cheap services, and waited until roots were deep enough; then they would change the billing scheme multiplying fees by up to 25
Sun was always fair to me, so much so that I feel like it's unfair to lump them together.
I used Solaris on Sun Fire machines and the support was unmatched, we got massive tome manuals that described in excruciating detail exactly how the system worked in almost all scenarios and a deep programming reference.
They never upselled us on anything, or changed the price.. until Oracle bought them and jacked the support costs up (though, to be perfectly fair, they ought to jack the support costs of old systems up).
