The scale of your operation and license subscriptions matters for the level of support you receive, naturally.
Big Microsoft shops, like state governments routinely have Microsoft staff fly out and work closely to bring new services online, etc. You cannot expect that level of service if you're just paying for a single database instance, of course.
IBM's support is also legendary - you will get a person on the phone at 3am, and even have a service technician onsite in the morning if needed. Personal experience with this one - they'll fly someone in from out of state to replace a hard drive if it means meeting their service levels.
Big Microsoft shops, like state governments routinely have Microsoft staff fly out and work closely to bring new services online, etc. You cannot expect that level of service if you're just paying for a single database instance, of course.
IBM's support is also legendary - you will get a person on the phone at 3am, and even have a service technician onsite in the morning if needed. Personal experience with this one - they'll fly someone in from out of state to replace a hard drive if it means meeting their service levels.