Do we need a full featured OS, or will a mobile one be enough?

Do I need Windows 8 and OSX or will iOS (or any Mobile OS) be enough?

With all these beautiful Windows 8 tablets and notebooks being just around the corner I keep wondering what sort of system I actually need to do all the things I need doing.

Is a Mobile Version enough for me? Will I be able to do all my work on a single device?

Sure I still need a big screen and a keyboard for some things, but in daily life I prefer to use 1 device.

I ask because Microsoft is making huge leaps forward and seems to have created a Mobile OS that is the complete thing (I don't refer to RT) that has it all. It's not missing options or features, it's not saying:

"You can do most of the things you want to do"

It's 100% Windows (well, 99.98% for missing a certain button ;)

What it comes down to is this: I don't think I can use an OS as my daily driver if I don't feel in control of that system.

Windows 8 = 100% iOS = 60% (even though it has OSX kernel, it's not OSX is it)

Am I the only one that needs full control of their OS? Will iOS6 change this for me, or will iOS never be open enough to give users the experience of being "in control".

Do I need to change and have peace with the Apple way of getting rid of the filesystem or will I be switching back to Microsoft?

(if they get Office to work on a tablet, is that enough?)

What do you think? Full OS or Mobile Version