rackspace.com is what your searching for.
but, ...you'll pay for that kind of quality. From their 100% uptime gaurantee, to their network infrastructure, to their 24/7 support, it's not cheap.
Hosting is a part of this business that's to important to deal with any other form of communication but the phone when there's a problem...unless the issue is minor ofcourse. But even then, i would rather talk to someone.
Support is at the phone 24/7, 365 days a year, waiting to work. Always there, no matter what. Their slogan is 'fanatical support.' Obviously you can email, or use their ticketing system, but why. Just pick up the phone.
Been with them a bit over 6 years. The only time i've ever been down all these years is when I do something stupid...like try and play admin or something.