work pc (currently mid-2012 MBA)

About to pass my mid-2012 MBA down the totem poll and get a new laptop.

The bootcamp MBA was ok, but the proprietary keyboard caused issues with our IBM CMS, and updating video drivers was risky. So i don't want another mac.

Currently considering:

Yoga 2
Surface Pro 2
Acer s7
Samsung Ativ Book 9

I only work out of the office a few days a week. The rest of the week can be home office, hotel, starbucks, etc.

Right now I'm thinking Surface Pro 2 for extreme portability and nice docking accessory, penning is also bonus. Currently i've been typing on the laptop keyboard, but with something like the Surface it would make a lot of sense to dock and then have two large monitors, keyboard and mouse. When unable to dock, the small screen may not be ideal. Keyboard cover and typing from lap I actually prefer to regular laptop.

The other options i consider to be the equivalent in weight and design to MBA, which is really the minimum goal of this laptop, to not be a downgrade from my MBA.

Anyone use any of the above as a primary/work computer? Any good alternatives?

No real budget, but hope to keep everything around $1200 or less.